![Engineering corps traian s column river crossing](https://upload.wikimedia.org/wikipedia/commons/d/d3/Engineering_corps_traian_s_column_river_crossing.jpg)
The (, lit. "auxiliaries") were introduced as non-citizen troops attached to the citizen
legions by
Augustus
Caesar Augustus (born Gaius Octavius; 23 September 63 BC – 19 August AD 14), also known as Octavian, was the first Roman emperor; he reigned from 27 BC until his death in AD 14. He is known for being the founder of the Roman Pr ...
after his reorganisation of the
Imperial Roman army
The Imperial Roman army was the military land force of the Roman Empire from about 30 BC to 476 AD, and the final incarnation in the long history of the Roman army. This period is sometimes split into the Principate (30 BC – 284 AD) and the Do ...
from 30 BC. By the 2nd century, the Auxilia contained the same number of infantry as the legions and, in addition, provided almost all of the Roman army's
cavalry (especially
light cavalry and
archers
Archery is the sport, practice, or skill of using a bow to shoot arrows.Paterson ''Encyclopaedia of Archery'' p. 17 The word comes from the Latin ''arcus'', meaning bow. Historically, archery has been used for hunting and combat. In mo ...
) and more specialised troops. The ''auxilia'' thus represented three-fifths of Rome's regular land forces at that time. Like their legionary counterparts, auxiliary recruits were mostly volunteers, not conscripts.
The Auxilia were mainly recruited from the ''
peregrini'', free provincial subjects who did not hold
Roman citizenship
Citizenship in ancient Rome (Latin: ''civitas'') was a privileged political and legal status afforded to free individuals with respect to laws, property, and governance. Citizenship in Ancient Rome was complex and based upon many different laws, t ...
and constituted the vast majority of the population in the 1st and 2nd centuries (c. 90% in the early 1st century). In contrast to the legions, which only admitted
Roman citizens
Citizenship in ancient Rome (Latin: ''civitas'') was a privileged political and legal status afforded to free individuals with respect to laws, property, and governance. Citizenship in Ancient Rome was complex and based upon many different laws, t ...
, members of the Auxilia could be recruited from territories outside of Roman control.
Reliance on the various contingents of non-
Italic troops, especially cavalry, increased when the
Roman Republic
The Roman Republic ( la, Res publica Romana ) was a form of government of Rome and the era of the classical Roman civilization when it was run through public representation of the Roman people. Beginning with the overthrow of the Roman Ki ...
employed them in increasing numbers to support its legions after 200 BC. The
Julio-Claudian
, native_name_lang=Latin, coat of arms=Great_Cameo_of_France-removebg.png, image_size=260px, caption= The Great Cameo of France depicting emperors Augustus, Tiberius, Claudius and Nero, type=Ancient Roman dynasty, country= Roman Empire, estates=* ...
period (30 BC–68 AD) saw the transformation of the Auxilia from motley
levies to a standing corps with standardised structure, equipment and conditions of service. By the end of the period, there were no significant differences between legionaries and auxiliaries in terms of training, and thus, combat capability.
Auxiliary regiments were often stationed in provinces other than that in which they were originally raised, for reasons of security and to foster the process of
Romanization
Romanization or romanisation, in linguistics, is the conversion of text from a different writing system to the Roman (Latin) script, or a system for doing so. Methods of romanization include transliteration, for representing written text, a ...
in the provinces. The regimental names of many auxiliary units persisted into the 4th century, but by then the units in question were different in size, structure, and quality from their predecessors.
Historical development
Background: Roman Republic (to 30 BC)
The mainstay of the Roman republic's war machine was the
manipular legion
Legion may refer to:
Military
* Roman legion, the basic military unit of the ancient Roman army
* Spanish Legion, an elite military unit within the Spanish Army
* Legion of the United States, a reorganization of the United States Army from 179 ...
, a
heavy infantry
Heavy infantry consisted of heavily armed and armoured infantrymen who were trained to mount frontal assaults and/or anchor the defensive center of a battle line. This differentiated them from light infantry who are relatively mobile and l ...
unit suitable for close-quarter engagements on more or less any terrain, which was probably adopted sometime during the
Samnite Wars
The First, Second, and Third Samnite Wars (343–341 BC, 326–304 BC, and 298–290 BC) were fought between the Roman Republic and the Samnites, who lived on a stretch of the Apennine Mountains south of Rome and north of the Lucanian tribe. ...
(343–290 BC). Despite its formidable strength, the legion had a number of deficiencies, especially a lack of cavalry. Around 200 BC, a legion of 4,200 infantry had a cavalry arm of only 300 horse (just 7% of the total force). This was because the class of citizens who could afford to pay for their own horse and equipment – the
equestrian order
The ''equites'' (; literally "horse-" or "cavalrymen", though sometimes referred to as "knights" in English) constituted the second of the property-based classes of ancient Rome, ranking below the senatorial class. A member of the equestrian ...
, the second rank in Roman society, after the
senatorial order – was relatively small. In addition, the legion lacked missile forces such as slingers and archers. Until 200 BC, the bulk of a Roman army's cavalry was provided by Rome's regular Italian allies (''
socii
The ''socii'' ( in English) or '' foederati'' ( in English) were confederates of Rome and formed one of the three legal denominations in Roman Italy (''Italia'') along with the Roman citizens (''Cives'') and the '' Latini''. The ''Latini'', who ...
''), commonly known as the "Latin" allies, which made up the
Roman military confederation
The ''socii'' ( in English) or ''foederati'' ( in English) were confederates of Rome and formed one of the three legal denominations in Roman Italy (''Italia'') along with the Roman citizens (''Cives'') and the '' Latini''. The ''Latini'', who w ...
. This was Rome's defence system until the
Social War of 91–88 BC. The Italian forces were organised into ''
alae'' (literally: "wings", because they were generally posted on the flanks of the Roman line of battle). An allied ''ala'', commanded by 3 Roman ''praefecti sociorum'', was similar or slightly larger in infantry size (4–5,000 men) to a legion, but contained a more substantial cavalry contingent: 900 horse, three times the legionary contingent. Since a pre-Social War
consular
A consul is an official representative of the government of one state in the territory of another, normally acting to assist and protect the citizens of the consul's own country, as well as to facilitate trade and friendship between the people ...
army always contained an equal number of legions and ''alae'', 75% of its cavalry was provided by the Latin allies. The overall cavalry element, c. 12% of the total force (2,400 out of a normal consular army of approximately 20,000 total effectives), was greater than in most peninsular Italian forces, but well below the overall 21% cavalry component that was typical of the Principate army (80,000 cavalry out of 380,000 total effectives in the early 2nd century).
[Holder (2003) 145][Hassall (2000) 320]
The Roman/Latin cavalry was sufficient while Rome was in conflict with other states in the mountainous Italian peninsula, which also disposed of limited cavalry resources. But, as Rome was confronted by external enemies that deployed far more powerful cavalry elements, such as the
Gauls
The Gauls ( la, Galli; grc, Γαλάται, ''Galátai'') were a group of Celtic peoples of mainland Europe in the Iron Age and the Roman period (roughly 5th century BC to 5th century AD). Their homeland was known as Gaul (''Gallia''). They s ...
and the Carthaginians, the Roman deficiency in cavalry numbers could be a serious liability, which in the
Second Punic War (218–202 BC) resulted in crushing defeats.
Hannibal's major victories at the
Trebia and at
Cannae, were owed to his Spanish and Gallic heavy cavalry, which far outnumbered the Roman and Latin levies, and to his
Numidians, light, fast cavalry which the Romans wholly lacked. The decisive Roman victory at
Zama in 202 BC, which ended the war, owed much to the
Numidian cavalry
Numidian cavalry was a type of light cavalry developed by the Numidians. After they were used by Hannibal during the Second Punic War, they were described by the Roman historian Livy as "by far the best horsemen in Africa."
History
Numidian cava ...
provided by king
Massinissa
Masinissa ( nxm, , ''MSNSN''; ''c.'' 238 BC – 148 BC), also spelled Massinissa, Massena and Massan, was an ancient Numidian king best known for leading a federation of Massylii Berber tribes during the Second Punic War (218–201 BC), ult ...
, which outnumbered the Roman/Latin cavalry fielded by 2 to 1. From then, Roman armies were always accompanied by large numbers of non-Italian cavalry: Numidian light cavalry and, later, Gallic heavy cavalry. For example, Caesar relied heavily on Gallic and German cavalry for his
Conquest of Gaul
The Gallic Wars were waged between 58 and 50 BC by the Roman general Julius Caesar against the peoples of Gaul (present-day France, Belgium, Germany and Switzerland). Gallic, Germanic, and British tribes fought to defend their homel ...
(58–51 BC).
[Goldsworthy (2000) 126]
As the role of native cavalry grew, that of Roman/Latin cavalry diminished. In the early 1st century BC, Roman cavalry was phased out altogether. After the Social War, the ''socii'' were all granted Roman citizenship, the Latin ''alae'' abolished, and the ''socii'' recruited into the legions. Furthermore, Roman equestrians were no longer required to perform cavalry service after this time. The late Republican legion was thus probably bereft of cavalry (a tiny cavalry force of 120 men was probably added back to the legion under
Augustus
Caesar Augustus (born Gaius Octavius; 23 September 63 BC – 19 August AD 14), also known as Octavian, was the first Roman emperor; he reigned from 27 BC until his death in AD 14. He is known for being the founder of the Roman Pr ...
).
![Slingers on Trajan's Column](https://upload.wikimedia.org/wikipedia/commons/5/54/Slingers_on_Trajan%27s_Column.JPG)
By the outbreak of the Second Punic War, the Romans were remedying the legions' other deficiencies by using non-Italian specialised troops. Livy reports
Hiero of
Syracuse offering to supply Rome with archers and slingers in 217 BC. From 200 BC onwards, specialist troops were hired as
mercenaries on a regular basis: ''
sagittarii
''Sagittarii'' (Latin, plural form of ''sagittarius'') is the Latin term for archers. The term ''sagittariorum'' in the title of an infantry or cavalry unit indicated a specialized archer regiment. Regular auxiliary units of foot and horse arc ...
'' (archers) from
Crete
Crete ( el, Κρήτη, translit=, Modern: , Ancient: ) is the largest and most populous of the Greek islands, the 88th largest island in the world and the fifth largest island in the Mediterranean Sea, after Sicily, Sardinia, Cyprus, ...
, and ''funditores'' (
slingers) from the
Balearic Isles
The Balearic Islands ( es, Islas Baleares ; or ca, Illes Balears ) are an archipelago in the Balearic Sea, near the eastern coast of the Iberian Peninsula. The archipelago is an autonomous community and a province of Spain; its capital is ...
almost always accompanied Roman legions in campaigns all over the Mediterranean.
The other main sources of non-Italian troops in the late Republic were subject provincials, allied cities and Rome's ''amici'' (satellite kings). During the late Republic, non-Italian units were led by their own native chiefs, and their internal organisation was left to their own commanders. The units varied widely in dress, equipment, and weapons. They were normally raised for specific campaigns and often disbanded soon afterwards, in a similar manner to the earlier ''socii'' militia legions.
Foundation of the auxilia under Augustus (30 BC–14 AD)
It appears that not all indigenous units were disbanded at the end of the civil war period (31 BC). Some of the more experienced units were kept in existence to complement the legions, and became the core of the standing auxiliary forces that developed in the Julio-Claudian period. During the early part of Augustus' rule (27 BC onwards), the corps of regular Auxilia was created. It was clearly inspired by the Latin forces of the pre-Social War Republic, as a corps of non-citizen troops parallel to the legions. But there were fundamental differences, the same as between Republican and Augustan legions. The Latin forces of the Republic were made up of part-time conscripts in units that would be raised and disbanded for and after particular campaigns. The Augustan Auxilia were mainly volunteer professionals serving in permanent units.
The unit structure of the Auxilia also differed from the Latin ''alae'', which were like legions with a larger cavalry arm. However, Augustus organised the Auxilia into regiments the size of
cohorts (a tenth the size of legions), due to the much greater flexibility of the smaller unit size. Further, the regiments were of three types: ''
ala Ala, ALA, Alaa or Alae may refer to:
Places
* Ala, Hiiu County, Estonia, a village
* Ala, Valga County, Estonia, a village
* Ala, Alappuzha, Kerala, India, a village
* Ala, Iran, a village in Semnan Province
* Ala, Gotland, Sweden
* Alad, S ...
'' (cavalry), ''
cohors (peditata)'' (infantry) and ''
cohors equitata
A cohort (from the Latin ''cohors'', plural ''cohortes'', see wikt:cohors for full inflection table) was a standard tactical military unit of a Roman legion. Although the standard size changed with time and situation, it was generally compos ...
'' (mixed cavalry/infantry).
[Goldsworthy (2000) 127]
The evidence for the size of the Augustus' new units is not clearcut, with our most precise evidence dating to the 2nd century, by which time the unit strengths may have changed. ''Cohortes'' were likely modelled on legionary cohorts i.e. six ''centuriae'' of about 80 men each (total about 480 men). ''Alae'' were divided into ''
turma
A ''turma'' (Latin for "swarm, squadron", plural ''turmae''), (Greek: τούρμα) was a cavalry unit in the Roman army of the Republic and Empire. In the Byzantine Empire, it became applied to the larger, regiment-sized military-administrative ...
e'' (squadrons) of 30 (or 32) men, each under a ''
decurio
''Decurio'' was an official title in Ancient Rome, used in various connections:
* Decurion (administrative), a member of the senatorial order in the Italian towns under the administration of Rome, and later in provincial towns organized on the It ...
'' (literally: "leader of ten"). This title derives from the old Roman cavalry of the pre-Social War republic, in which each ''turma'' was under the command of three ''decuriones''. ''Cohortes equitatae'' were infantry ''cohortes'' with a cavalry contingent of four ''turmae'' attached.
Auxiliary regiments were now led by a ''praefectus'' (prefect), who could be either a native nobleman, who would probably be granted Roman citizenship for the purpose (e.g. the famous German war leader
Arminius gained Roman citizenship probably by serving as an auxiliary prefect before turning against Rome); or a Roman, either of
knightly rank, or a senior
centurion.
At the start of Augustus' sole rule (30 BC), the original core auxiliary units in the West were composed of warlike tribesmen from the Gallic provinces (especially
Gallia Belgica
Gallia Belgica ("Belgic Gaul") was a province of the Roman Empire located in the north-eastern part of Roman Gaul, in what is today primarily northern France, Belgium, and Luxembourg, along with parts of the Netherlands and Germany.
In 50 BC, a ...
, which then included the regions later separated to form the provinces
Germania Inferior
Germania Inferior ("Lower Germania") was a Roman province from AD 85 until the province was renamed Germania Secunda in the fourth century, on the west bank of the Rhine bordering the North Sea. The capital of the province was Colonia Agripp ...
and
Germania Superior), and from the Balkan provinces (
Dalmatia and
Illyricum). By 19 BC, the
Cantabrian and Asturian Wars were concluded, leading to the annexation of northern
Hispania
Hispania ( la, Hispānia , ; nearly identically pronounced in Spanish, Portuguese, Catalan, and Italian) was the Roman name for the Iberian Peninsula and its provinces. Under the Roman Republic, Hispania was divided into two provinces: Hisp ...
and
Lusitania. Judging by the names of attested auxiliary regiments, these parts of the Iberian peninsula soon became a major source of recruits. Then the Danubian regions were annexed:
Raetia
Raetia ( ; ; also spelled Rhaetia) was a province of the Roman Empire, named after the Rhaetian people. It bordered on the west with the country of the Helvetii, on the east with Noricum, on the north with Vindelicia, on the south-west ...
(annexed 15 BC),
Noricum
Noricum () is the Latin name for the Celtic kingdom or federation of tribes that included most of modern Austria and part of Slovenia. In the first century AD, it became a province of the Roman Empire. Its borders were the Danube to the north, ...
(16 BC),
Pannonia (9 BC) and
Moesia (6 AD), becoming, with Illyricum, the Principate's most important source of auxiliary recruits for its entire duration. In the East, where the Syrians already provided the bulk of the Roman army's archers, Augustus annexed
Galatia (25 BC) and
Judaea
Judea or Judaea ( or ; from he, יהודה, Standard ''Yəhūda'', Tiberian ''Yehūḏā''; el, Ἰουδαία, ; la, Iūdaea) is an ancient, historic, Biblical Hebrew, contemporaneous Latin, and the modern-day name of the mountainous so ...
: the former, a region in central Anatolia with a Celtic-speaking people, became an important source of recruits. In N. Africa, Egypt,
Cyrene, and
Numidia (25 BC) were added to the empire. Numidia (modern day Eastern Algeria) was home to the Numidians/Moors, the ancestors of today's
Berber people
, image = File:Berber_flag.svg
, caption = The Berber flag, Berber ethnic flag
, population = 36 million
, region1 = Morocco
, pop1 = 14 million to 18 million
, region2 = Algeria
, p ...
. Their light cavalry (''equites Maurorum'') was highly prized and had alternately fought and assisted the Romans for well over two centuries: they now started to be recruited into the regular Auxilia. Even more Mauri units were formed after the annexation of
Mauretania (NW Algeria, Morocco), the rest of the Berber homeland, in 44 AD by emperor
Claudius (ruled 41–54).
Recruitment was thus heavy throughout the Augustan period, with a steady increase in the number of units formed. By AD 23, the Roman historian
Tacitus
Publius Cornelius Tacitus, known simply as Tacitus ( , ; – ), was a Roman historian and politician. Tacitus is widely regarded as one of the greatest Roman historians by modern scholars.
The surviving portions of his two major works—the ...
records that there were roughly the same numbers of auxiliaries in service as there were legionaries. Since at this time there were 25 legions of c. 5,000 men each, the Auxilia thus amounted to c. 125,000 men, implying c. 250 auxiliary regiments.
Illyrian revolt (6–9 AD)
During the early Julio-Claudian period, many auxiliary regiments raised in frontier provinces were stationed in or near their home provinces, except during periods of major crises such as the
Cantabrian Wars
The Cantabrian Wars (29–19 BC) (''Bellum Cantabricum''), sometimes also referred to as the Cantabrian and Asturian Wars (''Bellum Cantabricum et Asturicum''), were the final stage of the two-century long Roman conquest of Hispania, in what tod ...
, when they were deployed temporarily in theatre. This carried the obvious risk if their own tribe or ethnic group rebelled against Rome (or attacked the Roman frontier from outside the Empire), auxiliary troops could be tempted to make common cause with them. The Romans would then be faced by an enemy that included units fully equipped and trained by themselves, thus losing their usual tactical advantages over tribal foes.
[Keppie (1996) 396]
The German leader
Arminius is the classic example at an individual level: after several years of serving in Rome's forces as prefect of an auxiliary unit, he used the military training and experience he had gained to lead a confederacy of German tribes against Rome, culminating in the destruction of three Roman legions in the
Teutoberg Forest
The Teutoburg Forest ( ; german: Teutoburger Wald ) is a range of low, forested hills in the German states of Lower Saxony and North Rhine-Westphalia. Until the 17th century, the official name of the hill ridge was Osning. It was first renamed th ...
in 9 AD, and the abandonment of Augustus' strategy of annexing Germany as far as the
Elbe
The Elbe (; cs, Labe ; nds, Ilv or ''Elv''; Upper and dsb, Łobjo) is one of the major rivers of Central Europe. It rises in the Giant Mountains of the northern Czech Republic before traversing much of Bohemia (western half of the Czech Re ...
river. (This strategy was never revived by later emperors).
At a collective level, the risk was even greater, as the hugely dangerous
Illyrian revolt proved. The central Illyrian tribes were tough and spartan shepherds of the
Bosnian mountains and excellent soldier-material. Their territory formed part of the strategic province of Illyricum, recently expanded to include the territory of the
Pannonii, Celticised Illyrian tribes based on the west bank of the
Danube
The Danube ( ; ) is a river that was once a long-standing frontier of the Roman Empire and today connects 10 European countries, running through their territories or being a border. Originating in Germany, the Danube flows southeast for , p ...
who were subjugated by Rome in 12–9 BC (the ''Bellum Pannonicum''). By the start of the Common Era, they were an important recruitment base for the auxilia. But discontent was festering among the Illyrian tribes, largely due to what they saw as the rapacity of Roman tax officials. In AD 6, several regiments of
Dalmatae
The Delmatae, alternatively Dalmatæ, during the Roman period, were a group of Illyrian tribes in Dalmatia, contemporary southern Croatia and western Bosnia and Herzegovina. The region of Dalmatia takes its name from the tribe.
The Delmatae ap ...
, a warlike Illyrian tribe, were ordered to report to a designated location to prepare to join Augustus' stepson and senior military commander
Tiberius
Tiberius Julius Caesar Augustus (; 16 November 42 BC – 16 March AD 37) was the second Roman emperor. He reigned from AD 14 until 37, succeeding his stepfather, the first Roman emperor Augustus. Tiberius was born in Rome in 42 BC. His father ...
in a war against the Germans. Instead, they mutinied at the assembly point, and defeated a Roman force sent against them. The Dalmatae were soon joined by the
Breuci, another Illyrian tribe that supplied several auxiliary regiments. They gave battle to a second Roman force from
Moesia. They lost, but inflicted heavy casualties. The rebels were now joined by a large number of other Illyrian tribes. The Dalmatae attacked the port of
Salona
Salona ( grc, Σάλωνα) was an ancient city and the capital of the Roman province of Dalmatia. Salona is located in the modern town of Solin, next to Split, in Croatia.
Salona was founded in the 3rd century BC and was mostly destroyed in ...
and overran the Adriatic coast, defeating a Roman force and exposing the Roman heartland of Italy to the fear of a rebel invasion.
Augustus ordered Tiberius to break off operations in Germany and move his main army to Illyricum. When it became clear that even Tiberius' forces were insufficient, Augustus was obliged to raise a second task force under Tiberius' nephew
Germanicus, resorting to the compulsory purchase and emancipation of thousands of slaves to find enough troops, for the first time since the aftermath of the Battle of Cannae over two centuries earlier. The Romans had now deployed no less than 15 legions and an equivalent number of auxilia.
[Suetonius III.16] This amounts to a total of c. 150,000 men, including at least 50 auxiliary cohorts composed, exceptionally, of Roman citizens. These were men whose status or background was regarded by Augustus as unsuitable for recruitment into the legions: either natural-born citizens of the lowest category, including vagrants and convicted criminals, or the freed slaves (Roman law accorded citizenship to the freed slaves of Roman citizens). These special units were accorded the title ''civium Romanorum'' ("of Roman citizens"), or ''c.R.'' for short. After the Illyrian revolt, these cohorts remained in being and recruited non-citizens like other auxiliary units, but retained their prestigious ''c.R.'' title.
In addition, the regular forces were assisted by a large number of allied troops from neighbouring
Thrace
Thrace (; el, Θράκη, Thráki; bg, Тракия, Trakiya; tr, Trakya) or Thrake is a geographical and historical region in Southeast Europe, now split among Bulgaria, Greece, and Turkey, which is bounded by the Balkan Mountains to ...
deployed by their king
Rhoemetalces I
Rhoemetalces I (Sapaean) ( grc, Ῥοιμητάλκης) was king of the Sapaean kingdom of Thrace from 15 BC to 12 AD. He was king of Odrysian kingdom of Thrace in succession to his nephew Rhescuporis II (Astaean).
Rhoemetalces I was a loya ...
, a Roman ''amicus'' (puppet king).
The Romans faced further reverses on the battlefield and a savage guerrilla war in the Bosnian mountains. It took them three years of hard fighting to quell the revolt, which was described by the Roman historian
Suetonius, writing in c. AD 100, as the most difficult conflict faced by Rome since the
Punic Wars over two centuries earlier.
Tiberius finally succeeded in quelling the revolt in 9 AD. This was apparently lucky timing for the Romans: that same year Arminius destroyed
Varus' three legions in Germany. The Roman high command had no doubt that Arminius would have formed a grand alliance with the Illyrians.
Despite the gravity of this rebellion, the Illyrians went on, alongside their neighbours the Thracians, to become the backbone of the Roman army. By the 2nd century, with roughly half the Roman army deployed on the Danube frontier, the auxilia and legions alike were dominated by Illyrian recruits. In the 3rd century, Illyrians largely replaced Italians in the senior officer echelons of ''praefecti'' of auxiliary regiments and ''tribuni militum'' of legions. Finally, from AD 268 to 379, virtually all emperors, including
Diocletian and
Constantine the Great
Constantine I ( , ; la, Flavius Valerius Constantinus, ; ; 27 February 22 May 337), also known as Constantine the Great, was Roman emperor from AD 306 to 337, the first one to convert to Christianity. Born in Naissus, Dacia Mediterran ...
, were Romanised Illyrians from the provinces of
Dalmatia,
Moesia Superior and
Pannonia. These were members of a military aristocracy, outstanding soldiers who saved the empire from collapse in the turbulent late 3rd century.
Later Julio-Claudians (14–68 AD)
![Roman helmet](https://upload.wikimedia.org/wikipedia/commons/1/12/Roman_helmet.jpg)
Significant development of the Auxilia appears to have taken place during the rule of the emperor
Claudius (41–54 AD).
A minimum term of service of 25 years was established, at the end of which the retiring auxiliary soldier, and all his children, were awarded Roman citizenship.
[Keppie (1996) 391] This is deduced from the fact that the first known
Roman military diploma
A Roman military diploma was a document inscribed in bronze certifying that the holder was honourably discharged from the Roman armed forces and/or had received the grant of Roman citizenship from the emperor as reward for service.
The diploma ...
s date from the time of Claudius. This was a folding bronze tablet engraved with the details of the soldier's service record, which he could use to prove his citizenship. Claudius also decreed that prefects of auxiliary regiments must all be of equestrian rank, thus excluding centurions from such commands.
The fact that auxiliary commanders were now all of the same social rank as most ''
tribuni militum'', (military tribunes, a legion's senior staff officers, all of whom only one, the ''tribunus laticlavius'', was of the higher senatorial rank), probably indicates that auxilia now enjoyed greater prestige. Indigenous chiefs continued to command some auxiliary regiments, and were probably granted equestrian rank for the purpose. It is also likely that auxiliary pay was standardised at this time, but we only have estimates for the Julio-Claudian period.
Auxiliary uniform, armour, weapons and equipment were probably standardised by the end of the Julio-Claudian period. Auxiliary equipment was broadly similar to that of the legions (see
Section 2.1 below for possible differences in armour). By 68 AD, there was little difference between most auxiliary infantry and their legionary counterparts in equipment, training and fighting capability. The main difference was that auxilia contained combat cavalry, both heavy and light, and other specialized units that legions lacked.
Claudius annexed to the empire three regions that became important sources of auxiliary recruits:
Britannia
Britannia () is the national personification of Britain as a helmeted female warrior holding a trident and shield. An image first used in classical antiquity, the Latin ''Britannia'' was the name variously applied to the British Isles, Great ...
(43 AD), and the former client kingdoms of
Mauretania (44) and
Thracia
Thracia or Thrace ( ''Thrakē'') is the ancient name given to the southeastern Balkan region, the land inhabited by the Thracians. Thrace was ruled by the Odrysian kingdom during the Classical and Hellenistic eras, and briefly by the Greek D ...
(46). The latter became as important as Illyria as a source of auxiliary recruits, especially cavalry and archers. Britain in mid-2nd century contained the largest number of auxiliary regiments in any single province: about 60 out of about 400 (15%).
By the rule of
Nero
Nero Claudius Caesar Augustus Germanicus ( ; born Lucius Domitius Ahenobarbus; 15 December AD 37 – 9 June AD 68), was the fifth Roman emperor and final emperor of the Julio-Claudian dynasty, reigning from AD 54 unti ...
(54–68), auxiliary numbers may have reached, by one estimate, about 200,000 men, implying about 400 regiments.
Revolt of the Batavi (69–70 AD)
![Germania 70](https://upload.wikimedia.org/wikipedia/commons/4/49/Germania_70.svg)
The
Batavi, a Germanic tribe, inhabited the region today known as
Gelderland
Gelderland (), also known as Guelders () in English, is a province of the Netherlands, occupying the centre-east of the country. With a total area of of which is water, it is the largest province of the Netherlands by land area, and second by ...
(
Netherlands
)
, anthem = ( en, "William of Nassau")
, image_map =
, map_caption =
, subdivision_type = Sovereign state
, subdivision_name = Kingdom of the Netherlands
, established_title = Before independence
, established_date = Spanish Netherl ...
), in the Rhine river
delta
Delta commonly refers to:
* Delta (letter) (Δ or δ), a letter of the Greek alphabet
* River delta, at a river mouth
* D ( NATO phonetic alphabet: "Delta")
* Delta Air Lines, US
* Delta variant of SARS-CoV-2 that causes COVID-19
Delta may also ...
, then known as the ''Insula Batavorum'' ("Island of the Batavi", because surrounded by branches of the Rhine), part of the Roman province of
Germania Inferior
Germania Inferior ("Lower Germania") was a Roman province from AD 85 until the province was renamed Germania Secunda in the fourth century, on the west bank of the Rhine bordering the North Sea. The capital of the province was Colonia Agripp ...
.
[Tacitus ''Historiae'' IV.18] They were a warlike people, skilled horsemen, boatmen and swimmers. In return for the unusual privilege of exemption from ''tributum'' (direct taxes on land and heads normally exacted from ''peregrini''), they supplied a disproportionate number of recruits to the Julio-Claudian auxilia: one ''ala'' and eight ''cohortes''. They also provided most of Augustus' elite personal bodyguard unit (the ''Germani corpore custodes''), which continued in service until 68 AD. The Batavi auxilia amounted to about 5,000 men, implying that during the entire Julio-Claudian period, over 50% of all Batavi males reaching military age (16 years) may have enlisted in the auxilia.
[Birley (2002) 43] Thus the Batavi, although just 0.05% of the total population of the empire of c. 70 million in 23 AD, supplied about 4% of the total auxilia i.e. 80 times their proportionate share. They were regarded by the Romans as the very best (''fortissimi'', ''validissimi'') of their auxiliary, and indeed all, their forces. In Roman service, both their cavalry and infantry had perfected a technique for swimming across rivers wearing full armour and weapons.
Julius Civilis (literally: "Julius the Citizen", clearly a Latin name adopted on gaining
Roman citizenship
Citizenship in ancient Rome (Latin: ''civitas'') was a privileged political and legal status afforded to free individuals with respect to laws, property, and governance. Citizenship in Ancient Rome was complex and based upon many different laws, t ...
, not his native one) was a hereditary prince of the Batavi and the prefect of a Batavi cohort. A veteran of 25 years' service, he had distinguished himself by service in Britain, where he and the eight Batavi cohorts had played a crucial role in both the
Roman invasion in 43 AD and the subsequent subjugation of southern Britain.
By 69, however, Civilis, the Batavi regiments and the Batavi people had become utterly disaffected with Rome. After the Batavi regiments were withdrawn from Britain to Italy in 66, Civilis and his brother (also a prefect) were arrested by the
governor of Germania Inferior on a fabricated accusation of sedition. The governor ordered his brother's execution, while Civilis, who as a Roman citizen had the right to appeal to the emperor, was sent to Rome in chains for judgement by Nero. He was released by Nero's overthrower and successor,
Galba, but the latter also disbanded the imperial bodyguard unit for their loyalty to Nero. This alienated several hundred crack Batavi troops, and indeed the whole Batavi nation who regarded it as a grave insult. At the same time, relations collapsed between the Batavi cohorts and the legion to which they had been attached since the invasion of Britain 25 years earlier (''
XIV Gemina''). Their mutual hatred erupted in open fighting on at least two occasions.
At this juncture, the Roman empire was convulsed by its first major civil war since the
Battle of Actium
The Battle of Actium was a naval battle fought between a maritime fleet of Octavian led by Marcus Agrippa and the combined fleets of both Mark Antony and Cleopatra VII Philopator. The battle took place on 2 September 31 BC in the Ionian Sea, ...
exactly a century earlier: the
Year of the Four Emperors
The Year of the Four Emperors, AD 69, was the first civil war of the Roman Empire, during which four emperors ruled in succession: Galba, Otho, Vitellius, and Vespasian. It is considered an important interval, marking the transition from the ...
(69–70 AD). The governor of Germania Inferior, ordered to raise more troops, outraged the Batavi by attempting to conscript more Batavi than the maximum stipulated in their treaty. The brutality and corruption of the Roman recruiting-centurions (including incidents of sexual assault on Batavi young men) brought already deep discontent in the Batavi homeland to the boil.
Civilis now led his people in open revolt. Initially, he claimed he was supporting the bid for power of
Vespasian
Vespasian (; la, Vespasianus ; 17 November AD 9 – 23/24 June 79) was a Roman emperor who reigned from AD 69 to 79. The fourth and last emperor who reigned in the Year of the Four Emperors, he founded the Flavian dynasty that ruled the Empi ...
, the general in command of the legions in
Syria, whom Civilis had probably befriended when both were involved in the Roman invasion of Britain 25 years earlier (Vespasian was then commander of the legion ''
II Augusta''). But the uprising soon became a bid for independence. Civilis exploited the fact that some legions were absent from the Rhine area due to the civil war, and the rest under-strength. In addition, the Roman commanders and their rank-and-file soldiers were divided by loyalty to rival emperors. Civilis quickly won the support of the Batavi's neighbours and kinsmen, the
Cananefates
The Cananefates, or Canninefates, Caninefates, or Canenefatae, meaning "leek masters", were a Germanic tribe, who lived in the Rhine delta, in western Batavia (later Betuwe), in the Roman province of '' Germania Inferior'' (now in the Dutch pr ...
, who in turn won over the
Frisii
The Frisii were an ancient Germanic tribe living in the low-lying region between the Rhine–Meuse–Scheldt delta and the River Ems, and the presumed or possible ancestors of the modern-day ethnic Dutch.
The Frisii lived in the coastal are ...
. First the rebel allies captured two Roman forts in their territory, and a cohort of
Tungri
The Tungri (or Tongri, or Tungrians) were a tribe, or group of tribes, who lived in the Belgic part of Gaul, during the times of the Roman Empire. Within the Roman Empire, their territory was called the ''Civitas Tungrorum''. They were described b ...
defected to Civilis. Then two legions sent against Civilis were defeated when their companion Batavi ''ala'' defected to his side.
The ''
Classis Germanica'' (Rhine flotilla), largely manned by Batavi, was seized by Civilis. Most importantly, the 8 Batavi cohorts stationed at Mainz with ''XIV Gemina'' mutinied and joined him, defeating at
Bonn
The federal city of Bonn ( lat, Bonna) is a city on the banks of the Rhine in the German state of North Rhine-Westphalia, with a population of over 300,000. About south-southeast of Cologne, Bonn is in the southernmost part of the Rhine-Ru ...
a Roman force that attempted to block their return to their homeland. By now, Civilis commanded at least 12 regiments (6,000 men) of Roman-trained and equipped auxiliary troops, as well as a much larger number of tribal levies. A number of German tribes from beyond the Rhine joined his cause. Several other German and Gallic units sent against him deserted, as the revolt spread to the rest of
Gallia Belgica
Gallia Belgica ("Belgic Gaul") was a province of the Roman Empire located in the north-eastern part of Roman Gaul, in what is today primarily northern France, Belgium, and Luxembourg, along with parts of the Netherlands and Germany.
In 50 BC, a ...
, including the Tungri,
Lingones
The Lingones (Gaulish: 'the jumpers') were a Gallic tribe of the Iron Age and Roman periods. They dwelled in the region surrounding the present-day city of Langres, between the provinces of Gallia Lugdunensis and Gallia Belgica.
Name
Attes ...
and
Treviri
The Trēverī (Gaulish: *''Trēueroi'') were a Celtic tribe of the Belgae group who inhabited the lower valley of the Moselle from around 150 BCE, if not earlier, until their displacement by the Franks. Their domain lay within the southern fring ...
tribes. He was able to destroy the two remaining legions in Germania Inferior, (''
V Alaudae'' and ''
XV Primigenia'').
By this stage, Rome's entire position on the Rhine and even in Gaul was imperiled. Their civil war over, the Romans mustered a huge task force of eight legions (five dispatched from Italy, two from Spain and one from Britain) to deal with Civilis. Its commander
Petillius Cerialis had to fight two difficult battles, at
Trier
Trier ( , ; lb, Tréier ), formerly known in English as Trèves ( ;) and Triers (see also names in other languages), is a city on the banks of the Moselle in Germany. It lies in a valley between low vine-covered hills of red sandstone in the ...
and
Xanten
Xanten (, Low Rhenish: ''Santen'') is a town in the state of North Rhine-Westphalia, Germany. It is located in the district of Wesel.
Xanten is known for the Archaeological Park, one of the largest archaeological open air museums in the wo ...
, before he could overrun the Batavi's homeland. Tacitus' surviving narrative breaks off as he describes a meeting on an island in the Rhine delta between Civilis and Cerialis to discuss peace terms. We do not know the outcome of this meeting or Civilis' ultimate fate. But, in view of his former friendship with Vespasian, who had already offered him a pardon, and the fact that the Romans still needed the Batavi levies, it is likely that the terms were lenient by Roman standards.
Petilius Cerialis took a number of reconstituted Batavi units with him to Britain, and the Batavi regiments continued to serve with special distinction in Britain and elsewhere for the rest of the 1st century and beyond. Even as late as 395, units with the Batavi name, although long since composed of recruits from all over the empire, were still classified as elite ''
palatini'', e.g. the ''equites Batavi seniores'' (cavalry) and ''auxilium Batavi seniores'' (infantry).
Flavian era (69–96 AD)
![Grave for Titus Flavius Bassus Römisch-Germanisches Museum Cologne](https://upload.wikimedia.org/wikipedia/commons/1/14/Grave_for_Titus_Flavius_Bassus_R%C3%B6misch-Germanisches_Museum_Cologne.jpg)
The revolt of the Batavi appears to have led to a significant change in the Roman government's policy on deployment of Auxilia. The revolt proved that in times of civil strife, when legions were far from their bases campaigning for rival claimants to the imperial throne, it was dangerous to leave provinces exclusively in the hands of auxiliary regiments recruited from the indigenous nation. During the Julio-Claudian period, auxiliary regiments had often been deployed away from their original home province.
But in the Flavian period (69–96), this appears to have become standard policy.
Thus in AD 70, five reconstituted Batavi regiments (one ''ala'' and four ''cohortes'') were transferred to Britain under Petillius Cerialis, who had suppressed the Civilis revolt and then embarked on the governorship of the island. The great majority of regiments probably founded in the 1st century were stationed away from their province of origin in the second e.g. of 13 British regiments recorded in the mid-2nd century, none were stationed in Britain. Furthermore, it appears that in the Flavian era native noblemen were no longer permitted to command auxiliary units from their own tribe.
After a prolonged period in a foreign province a regiment would become assimilated, since the majority of its new recruits would be drawn from the province in which it was stationed, or neighbouring provinces.
Those same "British" units, mostly based on the Danube frontier, would by c. 150, after almost a century away from their home island, be largely composed of Illyrian, Thracian and Dacian recruits. However, there is evidence that a few regiments at least continued to draw some recruits from their original home provinces in the 2nd century e.g. Batavi units stationed in Britain.
[Mattingly (2006) 168–9]
The Flavian period also saw the first formation of large, double-size units, both infantry and cavalry, of a nominal strength of 1,000 men (''cohors/ala milliaria''), though they were actually mostly smaller (720 for an ''ala milliaria'' and 800 for a ''cohors milliaria'').
These were the mirror image of the double-strength first cohorts of legions also introduced at this time. Such units remained a minority of the Auxilia: in the mid-2nd century, they constituted 13% of units, containing 20% of total manpower.
[Hassall (2000) 332–4]
Later Principate (97–284)
![Spatha end of second century 1](https://upload.wikimedia.org/wikipedia/commons/5/59/Spatha_end_of_second_century_1.jpg)
In 106 AD, emperor Trajan finally defeated the
Dacian kingdom of
Decebalus
Decebalus (), sometimes referred to as Diurpaneus, was the last Dacian king. He is famous for fighting three wars, with varying success, against the Roman Empire under two emperors. After raiding south across the Danube, he defeated a Roman invas ...
and annexed it as the Roman province of
Dacia Traiana
Roman Dacia ( ; also known as Dacia Traiana, ; or Dacia Felix, 'Fertile/Happy Dacia') was a province of the Roman Empire from 106 to 271–275 AD. Its territory consisted of what are now the regions of Oltenia, Transylvania and Banat (today ...
. By the mid-2nd century, there were 44 auxiliary regiments stationed there, about 10% of the total auxilia. In Britain, there were 60. Together, these two provinces contained about a quarter of the total auxiliary regiments.
There is considerable scholarly dispute about the precise size of the auxilia during the imperial era, even during the corp's best-documented period, the rule of Trajan's successor,
Hadrian (117–138). This is evident if one compares calculations by Spaul (2000) and Holder (2003):
NOTE: Manpower figures exclude officers (centurions and decurions), which would have numbered about 3,500 men overall.
In addition, Holder believes that a further 14 ''cohortes'', which are attested under Trajan, immediately before Hadrian's rule, but not during or after it, probably continued in existence, giving a total of 381 units and 225,000 effectives. The discrepancy between the two scholars is due to: (i) Interpretation of units with the same name and number, but attested in different provinces in the same period. Spaul tends to take a more cautious approach and to assume such are the same unit moving base frequently, while Holder tends to regard them as separate units which acquired the same number due to duplicated (or even triplicated) seriation. (ii) Assumptions about how many ''cohortes'' were ''equitatae''. Spaul accepts only those ''cohortes'' specifically attested as ''equitatae'' i.e., about 40% of recorded units. Holder estimates that at least 70% of ''cohortes'' contained cavalry contingents by the early 2nd century
Even according to the more conservative estimate, the auxilia were by this time significantly larger than the legions, which contained c. 155,000 effectives (28 legions of 5,500 men each) at this time, of which just 3,360 were cavalry. (For a detailed breakdown, see section 4:
Auxilia deployment in the 2nd century, below).
During the second half of the 2nd century, the Roman army underwent considerable further expansion, with the addition of five new legions (27,500 men) to a Principate peak of 33. A matching number of auxilia (i.e. c. 50 regiments, although only the names of around 25–30 have survived in the epigraphic record) were probably added, possibly reaching a peak of c. 440 regiments and around 250,000 effectives by the end of
Septimius Severus
Lucius Septimius Severus (; 11 April 145 – 4 February 211) was Roman emperor from 193 to 211. He was born in Leptis Magna (present-day Al-Khums, Libya) in the Roman province of Africa. As a young man he advanced through the customary suc ...
's rule (211 AD).
The likely growth of the Roman auxilia may be summarised as follows:
NOTE: Regular land forces only. Excludes citizen-militias, barbarian '' foederati'', and Roman navy effectives
During the 2nd century, some units with the new names ''numerus'' ("group") and ''vexillatio'' ("detachment") appear in the diploma record. Their size is uncertain, but was likely smaller than the regular ''alae'' and ''cohortes'', as originally they were probably detachments from the latter, acquiring independent status after long-term separation. As these units are mentioned in diplomas, they were presumably part of the regular auxiliary organisation. But ''numeri'' was also a generic term used for barbarian units outside the regular auxilia. (see section 2.4
Irregular units, below).
In 212, the ''
constitutio Antoniniana
The ''Constitutio Antoniniana'' (Latin for: "Constitution r Edictof Antoninus") (also called the Edict of Caracalla or the Antonine Constitution) was an edict issued in AD 212, by the Roman Emperor Caracalla. It declared that all free men in t ...
'' (Antonine decree) of emperor
Caracalla
Marcus Aurelius Antoninus (born Lucius Septimius Bassianus, 4 April 188 – 8 April 217), better known by his nickname "Caracalla" () was Roman emperor from 198 to 217. He was a member of the Severan dynasty, the elder son of Emperor S ...
granted Roman citizenship to all the free inhabitants of the Empire – the ''peregrini'' – thus abolishing their second-class status. But there is no evidence that the citizens-only rule for legions was also abolished at this time. The legions simply gained a much wider recruitment base, as they were now able to recruit any male free resident of the empire. Auxiliary units were now recruited mainly from Roman citizens, but probably continued to recruit non-citizen ''barbari'' from outside the Empire's borders.
[Goldsworthy (2003) 74] However, the citizens-only rule for legions appears to have been dropped some time during the 3rd century, as by the 4th-century Romans and barbarians are found serving together in all units.
[Elton (1996) 148–52]
In the mid to late 3rd century, the army was afflicted by a combination of military disasters and of pestilence, the so-called
Crisis of the Third Century
The Crisis of the Third Century, also known as the Military Anarchy or the Imperial Crisis (AD 235–284), was a period in which the Roman Empire nearly collapsed. The crisis ended due to the military victories of Aurelian and with the ascensio ...
. In 251–271, Gaul, the Alpine regions and Italy, the Balkans and the East were simultaneously overrun by Alamanni, Sarmatians, Goths and Persians respectively. At the same time, the Roman army was struggling with the effects of a devastating pandemic, probably of
smallpox
Smallpox was an infectious disease caused by variola virus (often called smallpox virus) which belongs to the genus Orthopoxvirus. The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) c ...
: the
Plague of Cyprian
The Plague of Cyprian was a pandemic that afflicted the Roman Empire from about AD 249 to 262. The plague is thought to have caused widespread manpower shortages for food production and the Roman army, severely weakening the empire during the Crisi ...
, which began in 251 and was still raging in 270, when it claimed the life of emperor
Claudius II Gothicus
Marcus Aurelius Claudius "Gothicus" (10 May 214 – January/April 270), also known as Claudius II, was Roman emperor from 268 to 270. During his reign he fought successfully against the Alemanni and decisively defeated the Goths at the Battle ...
. The evidence for an earlier pandemic, the
Antonine Plague (also smallpox) indicates a mortality of 15–30% in the empire as a whole. The armies would likely have suffered deaths at the top end of the range, due to their close concentration of individuals and frequent movements across the empire. This probably led to a steep decline in military numbers, which only recovered at the end of the century under
Diocletian (r. 284–305).
[MacMullen (1979) 455]
The recruitment shortfall caused by the crisis seems to have led to recruitment of barbarians to the auxilia on a much greater scale than previously. By the 4th century, it has been estimated that some 25% of regular army recruits were barbarian-born. In the elite ''palatini'' regiments, anywhere between a third and a half of recruits may have been barbarian.
This is likely a much greater proportion of foreigners than joined the auxilia in the 1st and 2nd centuries. In the 3rd century, a small number of regular auxiliary units appear in the record that, for the first time, bear the names of barbarian tribes from outside the empire e.g. the ''ala I Sarmatarum'' attested in 3rd-century Britain. This was probably an offshoot of the 5,500 surrendered Sarmatian horsemen posted on
Hadrian's Wall by emperor
Marcus Aurelius
Marcus Aurelius Antoninus (Latin: áːɾkus̠ auɾέːli.us̠ antɔ́ːni.us̠ English: ; 26 April 121 – 17 March 180) was Roman emperor from 161 to 180 AD and a Stoic philosopher. He was the last of the rulers known as the Five Good ...
in c. 175. This unit may be an early example of a novel process whereby irregular units of ''barbari'' (''foederati'') were transformed into regular auxilia. This process intensified in the 4th century: the ''
Notitia Dignitatum'', a key document on the
late Roman army, lists a large number of regular units with barbarian names.
4th century
![Roman cavalry - Big Game Hunt mosaic - Villa Romana del Casale - Italy 2015](https://upload.wikimedia.org/wikipedia/commons/b/b5/Roman_cavalry_-_Big_Game_Hunt_mosaic_-_Villa_Romana_del_Casale_-_Italy_2015.JPG)
In the 4th century, the Roman army underwent a radical restructuring. In the rule of
Diocletian (284–305), the traditional Principate formations of ''legiones'', ''alae'' and ''cohortes'' appear to have been broken up into smaller units, many of which bore a variety of new names. Under
Constantine I
Constantine I ( , ; la, Flavius Valerius Constantinus, ; ; 27 February 22 May 337), also known as Constantine the Great, was Roman emperor from AD 306 to 337, the first one to Constantine the Great and Christianity, convert to Christiani ...
(r. 312–337) it appears that military units were classified into three grades based on strategic role and to some extent quality: ''
palatini'', elite units normally part of the ''exercitus praesentales'' (imperial escort armies); ''
comitatenses
The comitatenses and later the palatini were the units of the field armies of the late Roman Empire. They were the soldiers that replaced the legionaries, who had formed the backbone of the Roman military since the Marian reforms.
Organizati ...
'', higher-grade interception forces based in frontier provinces; and ''
limitanei
The ''līmitāneī'' (Latin, also called ''rīpēnsēs''), meaning respectively "the soldiers in frontier districts" (from the Latin phrase līmēs, meaning a military district of a frontier province) or "the soldiers on the riverbank" (from the ...
'', lower-grade border troops. (See
Late Roman army).
The old Principate auxilia regiments provided the basis for units at all three grades. The ''Notitia Dignitatum'' lists about 70 ''alae'' and ''cohortes'' that retained their 2nd-century names, mostly ''limitanei''. But traces of other auxilia regiments can be found in the ''praesentales'' and ''comitatenses'' armies. For example, many of the new-style ''
auxilia palatina ''Auxilia palatina'' (sing. ''auxilium palatinum'') were infantry units of the Late Roman army, first raised by Constantine I as part of the new field army he created in about 325 AD.
Some of the senior and probably oldest of these units had specia ...
'' infantry regiments, considered among the best units in the army, were probably formed from old-style auxiliary ''cohortes'', which they appear to closely resemble.
The late 4th-century writer on military affairs
Vegetius
Publius (or Flavius) Vegetius Renatus, known as Vegetius (), was a writer of the Later Roman Empire (late 4th century). Nothing is known of his life or station beyond what is contained in his two surviving works: ''Epitoma rei militaris'' (also r ...
complains of contemporary young men joining the "auxilia" in preference to the "legions" to avoid the latter's tougher training and duties. But it is unclear what types of units he was referring to. It is possible that those older terms were still popularly used (misleadingly) to mean ''limitanei'' and ''comitatenses'' respectively. In any event, his quote in no way describes accurately the Principate auxilia, many of which were of very high quality.
Unit types and structure
Regular unit types
The following table sets out the official, or establishment, strength of auxiliary units in the 2nd century. The real strength of a unit would fluctuate continually, but would likely have been somewhat less than the establishment most of the time.
* ''tribunus militum'' in original c.R. ''cohortes''[Birley (2002) 46]
** ''praefectus'' in Batavi and Tungri ''cohortes milliariae''
NOTE: Opinion is divided about the size of an ''ala'' ''turma'', between 30 and 32 men. 30 was the size of a ''turma'' in the Republican cavalry and in the ''cohors equitata'' of the Principate auxilia. Against this is a statement by Arrian that an ''ala'' was 512 strong. This would make an ala ''turma'' 32 men strong.
''Cohortes''
These all-infantry units were modeled on the cohorts of the legions, with the same officers and sub-units. They were typically considered to be more of a
light infantry
Light infantry refers to certain types of lightly equipped infantry throughout history. They have a more mobile or fluid function than other types of infantry, such as heavy infantry or line infantry. Historically, light infantry often fought ...
than proper legionaries. Some auxiliaries may however have been equipped with the ''
lorica segmentata
The ''lorica segmentata'' (), also called ''lorica lamminata'' (see Lorica segmentata#Name, §Name), is a type of personal armour that was used by soldiers of the Roman army, consisting of Laminar armor, metal strips fashioned into circular band ...
'', the most sophisticated legionary body-armour, although scholars dispute this. Besides this possibility, monuments (like on
Trajan's Column
Trajan's Column ( it, Colonna Traiana, la, Columna Traiani) is a Roman triumphal column in Rome, Italy, that commemorates Roman emperor Trajan's victory in the Dacian Wars. It was probably constructed under the supervision of the architect Ap ...
) show auxiliaries wearing chain mail armor, which length and form varied over the first and second century. They wore helmets similar to those of the Legion. Yet they seem to be simplified versions that where further improved over the same timeframe. They were equipped with a sword, a dagger and one or more spears or
javelins. This spear might have been a ''
lancea'', which can be used as a javelin as well as a thrusting spear. Based on archeological evidences auxiliaries probably had additional lighter javelins to their ''lancea''. The shield of the auxiliaries was oval.
There is no evidence that auxiliary infantry fought in a looser order than legionaries.
It appears that in a set-piece battle-line, auxiliary infantry would normally be stationed on the flanks, with legionary infantry holding the centre e.g. as in the
Battle of Watling Street
The Boudican revolt was an armed uprising by native Celtic tribes against the Roman Empire. It took place c. 60–61 AD in the Roman province of Britain, and was led by Boudica, the Queen of the Iceni. The uprising was motivated by the Romans' ...
(AD 60), the final defeat of the rebel Britons under queen
Boudicca
Boudica or Boudicca (, known in Latin chronicles as Boadicea or Boudicea, and in Welsh as ()), was a queen of the ancient British Iceni tribe, who led a failed uprising against the conquering forces of the Roman Empire in AD 60 or 61. She ...
. This was a tradition inherited from the Republic, when the precursors of auxiliary ''cohortes'', the Latin ''alae'', occupied the same position in the line.
[Goldsworthy (2000), p. 52] The flanks of the line required equal, if not greater, skill to hold as the centre.
''Alae''
During the
Principate
The Principate is the name sometimes given to the first period of the Roman Empire from the beginning of the reign of Augustus in 27 BC to the end of the Crisis of the Third Century in AD 284, after which it evolved into the so-called Dominate.
...
period of the
Roman Empire
The Roman Empire ( la, Imperium Romanum ; grc-gre, Βασιλεία τῶν Ῥωμαίων, Basileía tôn Rhōmaíōn) was the post- Republican period of ancient Rome. As a polity, it included large territorial holdings around the Mediter ...
(30 BC – AD 284), the all-mounted ''Alae'' ("wings") contained the elite cavalry of the army.
They were specially trained in elaborate manoeuvres, such as those displayed to the emperor Hadrian during a documented inspection in Numidia. They were best-suited for large-scale operations and battle, during which they acted as the primary cavalry escort for the legions, which had almost no cavalry of their own. Roman
alares were normally armoured, with mail or scale body armour, a cavalry version of the infantry helmet (with more protective features, such as completely covered ears) and oval shield or hexagonal. Their weapons could be a lance, javelins, or bow and arrow but all Roman horseman had a sword called a (''
spatha
The spatha was a type of straight and long sword, measuring between 0.5 and 1 m (19.7 and 39.4 in), with a handle length of between 18 and 20 cm (7.1 and 7.9 in), in use in the territory of the Roman Empire during the 1st to 6th centuries A ...
'') and the ubiquitous
pugio
The ''pugio'' (; plural: ''pugiones'') was a dagger used by Roman soldiers as a sidearm. It seems likely that the ''pugio'' was intended as an auxiliary weapon, but its exact purpose for the soldier remains unknown. Officials of the empire took t ...
. The elite status of an ''alaris'' is shown by the fact that he received 20% more pay than his counterpart in an auxiliary cohort or a legionary infantryman.
The favored sources of recruitment for the cavalry of the ''auxilia'' were
Gauls
The Gauls ( la, Galli; grc, Γαλάται, ''Galátai'') were a group of Celtic peoples of mainland Europe in the Iron Age and the Roman period (roughly 5th century BC to 5th century AD). Their homeland was known as Gaul (''Gallia''). They s ...
,
Germans
, native_name_lang = de
, region1 =
, pop1 = 72,650,269
, region2 =
, pop2 = 534,000
, region3 =
, pop3 = 157,000
3,322,405
, region4 =
, pop4 = ...
,
Iberians
The Iberians ( la, Hibērī, from el, Ἴβηρες, ''Iberes'') were an ancient people settled in the eastern and southern coasts of the Iberian peninsula, at least from the 6th century BC. They are described in Greek and Roman sources (amo ...
and
Thracians
The Thracians (; grc, Θρᾷκες ''Thrāikes''; la, Thraci) were an Indo-European speaking people who inhabited large parts of Eastern and Southeastern Europe in ancient history.. "The Thracians were an Indo-European people who occupied t ...
. All of these peoples had long-established skills and experience of fighting from horseback – in contrast to the Romans themselves. The ''alae'' were better paid and mounted than the more numerous horsemen of the ''cohortes equitatae'' (see below).
''Cohortes equitatae''
These were ''cohortes'' with a cavalry contingent attached. There is evidence that their numbers expanded with the passage of time. Only about 40% of attested ''cohortes'' are specifically attested as ''equitatae'' in inscriptions, which is probably the original Augustan proportion. A study of units stationed in Syria in the mid-2nd century found that many units that did not carry the ''equitata'' title did in fact contain cavalrymen e.g. by discovery of a tombstone of a cavalryman attached to the cohort. This implies that by that time, at least 70% of ''cohortes'' were probably ''equitatae''.
[Holder (2003), p. 119] The addition of cavalry to a cohort obviously enabled it to carry out a wider range of independent operations. A ''cohors equitata'' was in effect a self-contained mini-army.
The traditional view of ''equites cohortales'' (the cavalry arm of ''cohortes equitatae''), as expounded by G.L. Cheesman, was that they were just a mounted infantry with poor-quality horses. They would use their mounts simply to reach the battlefield and then would dismount to fight. This view is today discredited. Although it is clear that ''equites cohortales'' did not match ''equites alares'' (''ala'' cavalrymen) in quality (hence their lower pay), the evidence is that they fought as cavalry in the same way as the ''alares'' and often alongside them. Their armour and weapons were the same as for the ''alares''.
Nevertheless, non-combat roles of the ''equites cohortales'' differed significantly from the ''alares''. Non-combat roles such as despatch-riders (''dispositi'') were generally filled by cohort cavalry.
Auxiliary specialised units
In the Republican period, the standard trio of specialised auxilia were
Balearic slinger Balearic may refer to:
*Of the Balearic Islands
*The Balearic dialect of Catalan
*Balearic horse, a term sometimes used to describe either or both of these horse breeds in the region:
**Mallorquín
**Menorquín horse
The Menorquín or ca, ...
s, Cretan archers and Numidian light cavalry. These functions, plus some new ones, continued in the 2nd-century auxilia.
Heavily-armoured lancers
''
Equites cataphractarii
''Equites cataphractarii'', or simply ''cataphractarii'', were the most heavily armoured type of Roman cavalry in the Imperial Roman army and Late Roman army. The term derives from a Greek word, κατάφρακτος ''kataphraktos'', meaning " ...
'', or simply ''cataphractarii'' for short, were the heavily armoured cavalry of the
Roman army
The Roman army (Latin: ) was the armed forces deployed by the Romans throughout the duration of Ancient Rome, from the Roman Kingdom (c. 500 BC) to the Roman Republic (500–31 BC) and the Roman Empire (31 BC–395 AD), and its medieval contin ...
. Based on
Sarmatian
The Sarmatians (; grc, Σαρμαται, Sarmatai; Latin: ) were a large confederation of ancient Eastern Iranian equestrian nomadic peoples of classical antiquity who dominated the Pontic steppe from about the 3rd century BC to the 4th cen ...
and
Parthia
Parthia ( peo, 𐎱𐎼𐎰𐎺 ''Parθava''; xpr, 𐭐𐭓𐭕𐭅 ''Parθaw''; pal, 𐭯𐭫𐭮𐭥𐭡𐭥 ''Pahlaw'') is a historical region located in northeastern Greater Iran. It was conquered and subjugated by the empire of the Med ...
n models, they were also known as ''
contarii'' and ''
clibanarii
The Clibanarii or Klibanophoroi ( el, κλιβανοφόροι, meaning "camp oven-bearers" from the Greek word meaning "camp oven" or "metallic furnace"), in Persian Grivpanvar, were a Sasanian Persian, late Roman and Byzantine military unit of ...
'', although it is unclear whether these terms were interchangeable or whether they denoted variations in equipment or role. Together with new units of light mounted archers, the ''cataphractarii'' were designed to counter Parthian (and, in
Pannonia, Sarmatian) battle tactics. Parthian armies consisted largely of cavalry. Their standard tactic was to use light mounted archers to weaken and break up the Roman infantry line, and then to rout it with a charge by the ''cataphractarii'' concentrated on the weakest point. The only special heavy cavalry units to appear in the 2nd-century record are: ''ala I Ulpia contariorum'' and ''ala I Gallorum et Pannoniorum cataphractaria'' stationed in Pannonia and Moesia Inferior respectively in the 2nd century.
Light cavalry
From the Second Punic War until the 3rd century AD, the bulk of Rome's light cavalry (apart from mounted archers from Syria) was provided by the inhabitants of the provinces of
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
and
Mauretania Caesariensis, the Numidae or Mauri (from whom derives the English term "Moors"), who were the
ancestors
An ancestor, also known as a forefather, fore-elder or a forebear, is a parent or ( recursively) the parent of an antecedent (i.e., a grandparent, great-grandparent, great-great-grandparent and so forth). ''Ancestor'' is "any person from w ...
of the
Berber people
, image = File:Berber_flag.svg
, caption = The Berber flag, Berber ethnic flag
, population = 36 million
, region1 = Morocco
, pop1 = 14 million to 18 million
, region2 = Algeria
, p ...
of modern
Algeria
)
, image_map = Algeria (centered orthographic projection).svg
, map_caption =
, image_map2 =
, capital = Algiers
, coordinates =
, largest_city = capital
, relig ...
and
Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria t ...
. They were known as the ''
equites Maurorum'' or ''Numidarum'' ("Moorish or
Numidian cavalry
Numidian cavalry was a type of light cavalry developed by the Numidians. After they were used by Hannibal during the Second Punic War, they were described by the Roman historian Livy as "by far the best horsemen in Africa."
History
Numidian cava ...
"). On Trajan's Column, Mauri horsemen, depicted with long hair in dreadlocks, are shown riding their small but resilient horses bare-back and unbridled, with a simple braided rope round their mount's neck for control. They wear no body or head armour, carrying only a small, round leather shield. Their weaponry cannot be discerned due to stone erosion, but is known from Livy to have consisted of several short javelins. Exceptionally fast and maneuverable, Numidian cavalry would harass the enemy by hit-and-run attacks, riding up and loosing volleys of javelins, then scattering faster than any opposing cavalry could pursue. They were superbly suited to scouting, harassment, ambush and pursuit. It is unclear what proportion of the Numidian cavalry were regular auxilia units as opposed to irregular ''foederati'' units.
In the 3rd century, new formations of light cavalry appear, apparently recruited from the Danubian provinces: the ''
equites Dalmatae'' ("Dalmatian cavalry"). Little is known about these, but they were prominent in the 4th century, with several units listed in the ''Notitia Dignitatum''.
Camel troops
A unit of ''
dromedarii'' ("camel-mounted troops") is attested from the 2nd century, the ''ala I Ulpia dromedariorum milliaria'' in Syria.
Archers
A substantial number of auxiliary regiments (32, or about 1 in 12 in the 2nd century) were denoted ''sagittariorum'', or archer-units (from ''
sagittarii
''Sagittarii'' (Latin, plural form of ''sagittarius'') is the Latin term for archers. The term ''sagittariorum'' in the title of an infantry or cavalry unit indicated a specialized archer regiment. Regular auxiliary units of foot and horse arc ...
'' lit. "arrow-men", from ''sagitta'' = "arrow"). These 32 units (of which 4 were double-strength) had a total official strength of 17,600 men. All three types of auxiliary regiment (''ala'', ''cohors'' and ''cohors equitata'') could be denoted ''sagittariorum''. Although these units evidently specialised in archery, it is uncertain from the available evidence whether all ''sagittariorum'' personnel were archers, or simply a higher proportion than in ordinary units. At the same time, ordinary regiments probably also possessed some archers, otherwise their capacity for independent operations would have been unduly constrained. Bas-reliefs appear to show personnel in ordinary units employing bows.
From about 218 BC onwards, the archers of the
Roman army of the mid-Republic
The Roman army of the mid-Republic, also called the manipular Roman army or the Polybian army, refers to the armed forces deployed by the mid-Roman Republic, from the end of the Samnite Wars (290 BC) to the end of the Social War (88 BC). The fir ...
were virtually all mercenaries from the island of
Crete
Crete ( el, Κρήτη, translit=, Modern: , Ancient: ) is the largest and most populous of the Greek islands, the 88th largest island in the world and the fifth largest island in the Mediterranean Sea, after Sicily, Sardinia, Cyprus, ...
, which boasted a long specialist tradition. During the late Republic (88–30 BC) and the Augustan period, Crete was gradually eclipsed by men from other, much more populous, regions subjugated by the Romans with strong archery traditions. These included
Thrace
Thrace (; el, Θράκη, Thráki; bg, Тракия, Trakiya; tr, Trakya) or Thrake is a geographical and historical region in Southeast Europe, now split among Bulgaria, Greece, and Turkey, which is bounded by the Balkan Mountains to ...
,
Anatolia
Anatolia, tr, Anadolu Yarımadası), and the Anatolian plateau, also known as Asia Minor, is a large peninsula in Western Asia and the westernmost protrusion of the Asian continent. It constitutes the major part of modern-day Turkey. The ...
and, above all,
Syria. Of the 32 ''sagittarii'' units attested in the mid-2nd century, 13 have Syrian names, 7 Thracian, 5 from Anatolia, 1 from Crete and the remaining 6 of other or uncertain origin.
Three distinct types of archers are shown on Trajan's Column: (a) with scalar cuirass, conical steel helmet and cloak; (b) without armour, with cloth conical cap and long tunic; or (c) equipped in the same way as general auxiliary foot-soldiers (apart from carrying bows instead of javelins). The first type were probably Syrian or Anatolian units; the third type probably Thracian.
[Rossi (1971), p. 102] The standard bow used by Roman auxilia was the
recurved composite bow, a sophisticated, compact and powerful weapon.
[Goldsworthy (2003), p. 137]
Slingers
![Balearic Slinger](https://upload.wikimedia.org/wikipedia/commons/3/37/Balearic_Slinger.jpg)
From about 218 BC onwards, the Republican army's slingers were exclusively mercenaries from the
Balearic Islands, which had nurtured a strong indigenous tradition of slinging from prehistoric times. As a result, in classical Latin, ''Baleares'' (literally "inhabitants of the Balearic Islands") became an alternative word for "slingers" (''funditores'', from ''funda'' = "sling"). Because of this, it is uncertain whether most of the imperial army's slingers continued to be drawn from the Balearics themselves, or, like archers, derived mainly from other regions.
Independent slinger units are not attested in the epigraphic record of the Principate.
However, slingers are portrayed on Trajan's Column. They are shown unarmoured, wearing a short tunic. They carry a cloth bag, slung in front, to hold their shot (''glandes'').
Scouts/numeri
''Exploratores'' ('reconnaissance troops', from ''explorare'' = "to scout"). Two examples include ''numeri exploratorum'' attested to in the 3rd century in Britain: ''Habitanco'' and ''Bremenio'' (both names of forts). It is possible, however, that more than 20 such units served in Britain. The literal translation of ''numeri'' is 'numbers' and it was often used in the context of a generic title for any unit that was not of a standard size or structure. From the 2nd century onward they served as frontier guards, often supplied by the
Sarmatians
The Sarmatians (; grc, Σαρμαται, Sarmatai; Latin: ) were a large confederation of ancient Eastern Iranian equestrian nomadic peoples of classical antiquity who dominated the Pontic steppe from about the 3rd century BC to the 4th cen ...
and the
Germans
, native_name_lang = de
, region1 =
, pop1 = 72,650,269
, region2 =
, pop2 = 534,000
, region3 =
, pop3 = 157,000
3,322,405
, region4 =
, pop4 = ...
. Little else is known about such units.
Irregular allied forces
Throughout the Principate period, there is evidence of ethnic units of ''barbari'' outside the normal auxilia organisation fighting alongside Roman troops. To an extent, these units were simply a continuation of the old client-king levies of the late Republic: ''ad hoc'' bodies of troops supplied by Rome's puppet petty-kings on the imperial borders for particular campaigns. Some clearly remained in Roman service beyond the campaigns, keeping their own native leadership, attire and equipment and structure. These units were known to the Romans as ''socii'' ("allies"), ''symmachiarii'' (from ''symmachoi'', Greek for "allies") or ''
foederati'' ("treaty troops" from ''foedus'', "treaty"). One estimate puts the number of ''foederati'' in the time of Trajan at about 11,000, divided into about 40 ''numeri'' (units) of about 300 men each. The purpose of employing ''foederati'' units was to use their specialist fighting skills. Many of these would have been troops of Numidian cavalry (see
light cavalry above).
The ''foederati'' make their first official appearance on Trajan's Column, where they are portrayed in a standardised manner, with long hair and beards, barefoot, stripped to the waist, wearing long trousers held up by wide belts and wielding clubs. In reality, several different tribes supported the Romans in the Dacian wars. Their attire and weapons would have varied widely. The Column stereotypes them with the appearance of a single tribe, probably the most outlandish-looking, to differentiate them clearly from the regular auxilia. Judging by the frequency of their appearance in the Column's battle scenes, the ''foederati'' were important contributors to the Roman operations in Dacia. Another example of ''foederati'' are the 5,500 captured Sarmatian cavalrymen sent by Emperor
Marcus Aurelius
Marcus Aurelius Antoninus (Latin: áːɾkus̠ auɾέːli.us̠ antɔ́ːni.us̠ English: ; 26 April 121 – 17 March 180) was Roman emperor from 161 to 180 AD and a Stoic philosopher. He was the last of the rulers known as the Five Good ...
(r. 161–180) to garrison a fort on Hadrian's Wall after their defeat in the
Marcomannic Wars.
Recruitment, ranks and pay
The evidence for auxiliary ranks and pay is scant: even less exists than the patchy evidence for their legionary counterparts. There seems to be some consensus, however, that the auxiliary was paid one third of what a legionary received: 300 sesterces a year (400 after the reign of the emperor
Commodus). Both auxiliaries and seamen received the ''
viaticum
Viaticum is a term used – especially in the Catholic Church – for the Eucharist (also called Holy Communion), administered, with or without Anointing of the Sick (also called Extreme Unction), to a person who is dying; viaticum is thus a part ...
'' of 300 sesterces, although the various sources differ as to whether auxiliaries and sailors received the retirement bonus known as the ''
honesta missio
The ''honesta missio'' was the honorable discharge from the military service in the Roman Empire. The status conveyed particular privileges (''praemia militiae''). Among other things, an honorably discharged legionary was paid discharge money fr ...
'', or honorable discharge.
The available data may be broken down and summarised as follows:
Rankers (''caligati'')
![CohMont1](https://upload.wikimedia.org/wikipedia/commons/f/f2/CohMont1.jpg)
At the bottom end of the rank pyramid, rankers were known as ''caligati'' (lit: "sandal men" from the ''
caligae'' or hob-nailed sandals worn by soldiers). Depending on the type of regiment they belonged to, they held the official ranks of ''pedes'' (foot soldier in a ''cohors''), ''eques'' (cavalryman in a ''cohors equitata'') and ''gregalis'' (''ala'' cavalryman).
During the Principate, recruitment into the legions was restricted to Roman citizens only. This rule, which derived from the pre-Social War Republican army, was strictly enforced. The few exceptions recorded, such as during emergencies and for the illegitimate sons of legionaries, do not warrant the suggestion that the rule was routinely ignored.
In the 1st century, the vast majority of auxiliary common soldiers were recruited from the Roman ''
peregrini'' (
second-class citizen
A second-class citizen is a person who is systematically and actively discriminated against within a state or other political jurisdiction, despite their nominal status as a citizen or a legal resident there. While not necessarily slaves, o ...
s). In the Julio-Claudian era,
conscription of ''peregrini'' seems to have been practiced alongside voluntary recruitment, probably in the form of a fixed proportion of men reaching military age in each tribe being drafted.
[Holder (1980) 123] From the Flavian era onwards, the auxilia were an all-volunteer force. Although recruits as young as 14 are recorded, the majority of recruits (66%) were from the 18–23 age group.
When it was first raised, an auxiliary regiment would have been recruited from the native tribe or people whose name it bore. In the early Julio-Claudian period, it seems that efforts were made to preserve the ethnic integrity of units, even when the regiment was posted in a faraway province. But in the later part of the period, recruitment in the region where the regiment was posted increased and became predominant from the Flavian era onwards.
The regiment would thus lose its original ethnic identity.
The unit's name would thus become a mere curiosity devoid of meaning, although some of its members might inherit foreign names from their veteran ancestors. This view has to be qualified, however, as evidence from military diplomas and other inscriptions shows that some units continued to recruit in their original home areas e.g. Batavi units stationed in Britain, where some units had an international membership.
It also appears that the Danubian provinces (Raetia, Pannonia, Moesia, Dacia) remained key recruiting grounds for units stationed all over the empire.
It appears that Roman citizens were also regularly recruited to the auxilia. Most likely, the majority of citizen recruits to auxiliary regiments were the sons of auxiliary veterans who were enfranchised on their fathers' discharge. Many such may have preferred to join their fathers' old regiments, which were a kind of extended family to them, rather than join a much larger, unfamiliar legion. There are also instances of legionaries transferring to the auxilia (to a higher rank).
[Holder (1980) 86–8] The incidence of citizens in the auxilia would thus have grown steadily over time until, after the grant of citizenship to all ''peregrini'' in 212, auxiliary regiments became predominantly, if not exclusively, citizen units.
Less clearcut is the question of whether the regular auxilia recruited ''barbari'' (barbarians, as the Romans called people living outside the empire's borders). Although there is little evidence of it before the 3rd century, the consensus is that auxilia recruited barbarians throughout their history.
In the 3rd century, a few auxilia units of clearly barbarian origin start to appear in the record e.g. ''Ala I Sarmatarum'', ''cuneus Frisiorum'' and ''numerus Hnaufridi'' in Britain.
[Mattingly (2006) 223]
There existed a hierarchy of pay between types of auxiliary, with cavalry higher paid than infantry. One recent estimate is that in the time of Augustus, the annual pay structure was: ''eques alaris'' (''gregalis'') 263 ''denarii'', ''eques cohortalis'' 225, and ''cohors'' infantryman 188.
[Goldsworthy (2003) 94] The same differentials (of about 20% between grades) seem to have existed at the time of Domitian (r. 81–96).
[Hassall (2000) 336] However, Goldsworthy points out that the common assumption that rates of pay were universal across provinces and units is unproven. Pay may have varied according to the origin of the unit.
The remuneration of an auxiliary ''pedes cohortalis'' may be compared to a legionary's as follows:
Gross salary was subject to deductions for food, clothing, boots and hay (probably for the company mules). It is unclear whether the cost of armour and weapons was also deducted, or borne by the army. Deductions left the soldier with a net salary of 78 ''denarii''. This sum was sufficient, on the basis of the food deduction, to amply feed an adult for a year. In 84 AD
Domitian
Domitian (; la, Domitianus; 24 October 51 – 18 September 96) was a Roman emperor who reigned from 81 to 96. The son of Vespasian and the younger brother of Titus, his two predecessors on the throne, he was the last member of the Fl ...
increased basic legionary pay by 33% (from 225 to 300 ''denarii''): a similar increase was presumably accorded to auxiliaries, boosting their net income to 140 ''denarii'', i.e. more than two food allowances. It was entirely disposable, as the soldier was exempt from the
poll tax (''capitatio''), did not pay rent (he was housed in fort barracks) and his food, clothing and equipment were already deducted. It should be borne in mind that most recruits came from peasant families living at
subsistence level. To such persons, any disposable income would appear attractive. It could be spent on leisure activities, sent to relatives or simply saved for retirement.
There is no evidence that auxiliaries received the substantial cash bonuses (
donativum
The ''donativum'' (plural ''donativa'') was a gift of money by the Roman emperors to the soldiers of the Roman legions or to the Praetorian Guard. The English translation is '' donative''.
The purpose of the ''donativa'' varied. Some were expre ...
) handed to legionaries on the accession of a new emperor and other occasions.
[Goldsworthy (2003) 96] Although irregular, these payments (each worth 75 ''denarii'' to a common legionary) averaged once every 7.5 years in the early 1st century and every three years later. Duncan-Jones has suggested that ''donativa'' may have been paid to auxiliaries also from the time of Hadrian onwards, on the grounds that the total amount of donative to the military increased sharply at that time. A very valuable benefit paid to legionaries was the discharge bonus (''praemia'') paid on completion of the full 25 years' service. At 3,000 ''denarii'', this was equivalent to ten years' gross salary for a common legionary after the pay increase of 84 AD. It would enable him to purchase a substantial plot of land. Again, there is no indication that auxiliaries were paid a discharge bonus. For auxiliaries, the discharge bonus was the grant of Roman citizenship, which carried important tax exemptions. However, Duncan-Jones argues that the fact that service in the auxilia was competitive with the legions (deduced from the many Roman citizens that joined the auxilia) that a discharge bonus may have been paid.
Junior officers (''principales'')
Below centurion/decurion rank, junior officers in the Roman army were known as ''principales''. An auxiliary cohort's ranks appear the same as in a legionary ''centuria''. These were, in ascending order: ''tesserarius'' ("officer of the watch"), ''signifer'' (standard-bearer for the ''centuria''), ''optio'' (centurion's deputy) and ''vexillarius'' (standard-bearer for the whole regiment, from ''
vexillum
The ''vexillum'' (; plural ''vexilla'') was a flag-like object used as a military standard by units in the Ancient Roman army.
Use in Roman army
The word ''vexillum'' is a derivative of the Latin word, ''velum'', meaning a sail, which co ...
''). In the ''turmae'' of ''cohortes equitatae'' (and of ''alae''?), the decurion's second-in-command was probably known as a ''curator'', responsible for horses and caparison.
[Birley (2002) 47] As in the legions, the ''principales'', together with some regimental specialists, were classified in two pay-scales: ''sesquiplicarii'' ("one-and-a-half-pay men") and ''
duplicarii'' ("double-pay men").
These ranks are probably most closely resembled by the modern ranks of
corporal
Corporal is a military rank in use in some form by many militaries and by some police forces or other uniformed organizations. The word is derived from the medieval Italian phrase ("head of a body"). The rank is usually the lowest ranking non- ...
and
sergeant respectively.
Besides combat effectives, regiments also contained specialists, the most senior of whom were ''sesquiplicarii'' or ''duplicarii'', the rest common soldiers with the status of ''milities immunes'' ("exempt soldiers" i.e. exempt from normal duties). Ranking specialists included the ''medicus'' (regimental doctor), ''
veterinarius'' (veterinary doctor, in charge of the care of horses, pack animals and livestock), ''custos armorum'' (keeper of the armoury), and the ''cornicularius'' (clerk in charge of all the regiment's records and paperwork).
Senior officers
![Grabstein Titus Calidius Carnuntum](https://upload.wikimedia.org/wikipedia/commons/d/d3/Grabstein_Titus_Calidius_Carnuntum.jpg)
The limited evidence on auxiliary ''centuriones'' and ''decuriones'' is that such officers could be directly commissioned as well as promoted from the ranks. Many appear to have come from provincial aristocracies.
[Goldsworthy (2003) 73] Those rising from the ranks could be promotions from the legions as well as from the regiment's own ranks. In the Julio-Claudian period auxiliary ''centuriones'' and ''decuriones'' were a roughly equal split between citizens and ''peregrini'', though later citizens became predominant due to the spread of citizenship among military families.
Because ''centuriones'' and ''decuriones'' often rose from the ranks, they have often been compared to
warrant officer
Warrant officer (WO) is a rank or category of ranks in the armed forces of many countries. Depending on the country, service, or historical context, warrant officers are sometimes classified as the most junior of the commissioned ranks, the mos ...
s such as
sergeants-major in modern armies. However, centurions' social role was much wider than a modern warrant-officer. In addition to their military duties, centurions performed a wide range of administrative tasks, which was necessary in the absence of an adequate bureaucracy to support provincial governors. They were also relatively wealthy, due to their high salaries (see table above).
[Goldsworthy (2003) 72] However, most of the surviving evidence concerns legionary centurions and it is uncertain whether their auxiliary counterparts shared their high status and non-military role.
There is little evidence about the pay-scales of auxiliary ''centuriones'' and ''decuriones'', but these are also believed to have amounted to several times that of a ''miles''.
Unlike a ''
legatus legionis
A ''legatus'' (; anglicised as legate) was a high-ranking Roman military officer in the Roman Army, equivalent to a modern high-ranking general officer. Initially used to delegate power, the term became formalised under Augustus as the office ...
'' (who had an officer staff of 6 ''tribuni militum'' and one ''praefectus castrorum''), an auxiliary ''praefectus'' does not appear to have enjoyed the support of purely staff officers. The possible exception is an attested ''beneficiarius'' ("deputy"), who may have been the praefectus' second-in-command, if this title was a regular rank and not simply an ''ad hoc'' appointment for a specific task. Also attached to the ''praefectus'' were the regiment's ''vexillarius'' (standard-bearer for the whole unit) and ''cornucen'' (horn-blower).
Commanders
From a survey by Devijver of persons whose origin can be determined, it appears that during the 1st century, the large majority (65%) of auxiliary prefects were of Italian origin. The Italian proportion dropped steadily, to 38% in the 2nd century, and 21% in the 3rd century. From the time of emperor Claudius (r. 41–54) only Roman knights were eligible to hold command of an auxiliary regiment. This status could be obtained either by birth (i.e. if the person was the son of a hereditary Roman knight; or by attaining the property qualification (100,000 ''denarii'', the equivalent of 400 years' gross salary for an auxiliary ''alaris''); or by military promotion: the latter were the chief centurions of legions (''centurio primus pilus'') who would normally be elevated to equestrian rank by the emperor after completing their single-year term as ''primuspilus''.
[Goldsworthy (2003) 65–6]
Equestrians by birth would normally begin their military careers at c. 30 years of age. An axillary had to do 25 years of service before joining the army. Commands were held in a set sequence, each held for 3–4 years: prefect of an auxiliary ''cohors'', ''tribunus militum'' in a legion and finally prefect of an auxiliary ''ala''. In Hadrian's time, a fourth command was added, for exceptionally able officers, of prefect of an ''ala milliaria''. Like officers senatorial rank, hereditary equestrians held civilian posts before and after their decade of military service, whereas non-hereditary officers tended to remain in the army, commanding various units in various provinces. By the 3rd century, most auxiliary prefects had exclusively military careers.
The pay of a ''praefectus'' of an auxiliary regiment in the early 2nd century has been estimated at over 50 times that of a ''miles'' (common soldier).
(This compares to a full
colonel
Colonel (abbreviated as Col., Col or COL) is a senior military officer rank used in many countries. It is also used in some police forces and paramilitary organizations.
In the 17th, 18th and 19th centuries, a colonel was typically in charge o ...
in the British Army, who is currently paid about five times a private's salary). The reason for the huge gap between the top and the bottom of the pyramid is that Roman society was far more hierarchical than a modern one. A ''praefectus'' was not just a senior officer. He was also a Roman citizen (which most of his men were not) and, as a member of the equestrian order, an aristocrat. The social gulf between the ''praefectus'' and a ''peregrinus'' soldier was thus immense, and the pay differential reflected that fact.
Names, titles and decorations
Regimental names
The nomenclature of the great majority of regiments followed a standard configuration: unit type, followed by serial number, followed by name of the ''peregrini'' tribe (or nation) from whom the regiment was originally raised, in the genitive plural case e.g. ''cohors III Batavorum'' ("3rd Cohort of Batavi"); ''cohors I Brittonum'' ("1st Cohort of Britons"). Some regiments combine the names of two ''peregrini'' tribes, most likely after the merger of two previously separate regiments e.g. ''ala I Pannoniorum et Gallorum'' ("1st Wing of Pannonii and Gauls"). A minority of regiments are named after an individual, mostly after the first prefect of the regiment, e.g. ''ala Sulpicia'' (presumably named after a prefect whose middle (''gens'') name was Sulpicius). The latter is also an example of a regiment that did not have a serial number.
Titles
Regiments were often rewarded for meritorious service by the grant of an honorific title. The most sought-after was the prestigious ''c.R.'' (''civium Romanorum'' = "of Roman citizens") title. In the latter case, all the regiment's members at the time, but not their successors, would be granted Roman citizenship. But the regiment would retain the c.R. title in perpetuity. Another common title was the ''gens'' name of the emperor making the award (or founding the regiment) e.g. ''Ulpia'': the ''gens'' name of
Trajan
Trajan ( ; la, Caesar Nerva Traianus; 18 September 539/11 August 117) was Roman emperor from 98 to 117. Officially declared ''optimus princeps'' ("best ruler") by the senate, Trajan is remembered as a successful soldier-emperor who presi ...
(Marcus Ulpius Traianus r.98–117). Other titles were similar to those given to the legions e.g. ''pia fidelis'' (''p.f.'' = "dutiful and loyal").
[Goldsworthy (2003) 97]
Decorations
The Roman army awarded a variety of individual decorations (''dona'') for valour to its legionaries. ''Hasta pura'' was a miniature spear; ''phalerae'' were large medal-like bronze or silver discs worn on the cuirass; ''armillae'' were bracelets worn on the wrist; and
torques
In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of the ...
were worn round the neck, or on the cuirass. The highest awards were the ''coronae'' ("crowns"), of which the most prestigious was the ''corona civica'', a crown made of oak-leaves awarded for saving the life of a Roman citizen in battle. The most valuable award was the ''corona muralis'', a crown made of gold awarded to the first man to scale an enemy rampart. This was awarded rarely, as such a man hardly ever survived.
There is no evidence that auxiliary common soldiers received individual decorations, although auxiliary officers did. Instead, the whole regiment was honoured by a title reflecting the type of award e.g. ''torquata'' (awarded a torque) or ''armillata'' (awarded bracelets). Some regiments would, in the course of time, accumulate a long list of titles and decorations e.g. ''cohors I Brittonum Ulpia torquata pia fidelis c.R.''.
Deployment in the 2nd century
![Roman Empire 125](https://upload.wikimedia.org/wikipedia/commons/b/bb/Roman_Empire_125.png)
Notes: (1) Table excludes about 2,000 officers (centurions and above). (2) Auxiliary cavalry nos. assumes 70% of ''cohortes'' were ''equitatae''
Analysis
# The table shows the importance of auxiliary troops in the 2nd century, when they outnumbered legionaries by 1.5 to 1.
# The table shows that legions did not have a standard complement of auxiliary regiments
[Goldsworthy (2000)] and that there was no fixed ratio of auxiliary regiments to legions in each province. The ratio varied from six regiments per legion in Cappadocia to 40 per legion in Mauretania.
# Overall, cavalry represented about 20% (including the small contingents of legionary cavalry) of the total army effectives. But there were variations: in Mauretania the cavalry proportion was 28%.
# The figures show the massive deployments in Britannia and Dacia. Together, these two provinces account for 27% of the total auxilia corps.
See also
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Imperial Roman army
The Imperial Roman army was the military land force of the Roman Empire from about 30 BC to 476 AD, and the final incarnation in the long history of the Roman army. This period is sometimes split into the Principate (30 BC – 284 AD) and the Do ...
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Roman auxiliaries in Britain The overall size of the Roman forces in Roman Britain grew from about 40,000 in the mid 1st century AD to a maximum of about 55,000 in the mid 2nd century. The proportion of auxiliaries in Britain grew from about 50% before 69 AD to over 70% in c. ...
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Structural history of the Roman military
Citations
References
Ancient
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Arrian ''Acies contra Alanos'' (early 2nd century)
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Dio Cassius ''Roman History'' (mid-3rd century)
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Suetonius ''De vita Caesarum'' (early 2nd century)
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Tacitus
Publius Cornelius Tacitus, known simply as Tacitus ( , ; – ), was a Roman historian and politician. Tacitus is widely regarded as one of the greatest Roman historians by modern scholars.
The surviving portions of his two major works—the ...
''Agricola'' (end of 1st century)
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Tacitus
Publius Cornelius Tacitus, known simply as Tacitus ( , ; – ), was a Roman historian and politician. Tacitus is widely regarded as one of the greatest Roman historians by modern scholars.
The surviving portions of his two major works—the ...
''Annales'' (end of 1st century)
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Tacitus
Publius Cornelius Tacitus, known simply as Tacitus ( , ; – ), was a Roman historian and politician. Tacitus is widely regarded as one of the greatest Roman historians by modern scholars.
The surviving portions of his two major works—the ...
''Historiae'' (end of 1st century)
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Vegetius
Publius (or Flavius) Vegetius Renatus, known as Vegetius (), was a writer of the Later Roman Empire (late 4th century). Nothing is known of his life or station beyond what is contained in his two surviving works: ''Epitoma rei militaris'' (also r ...
''De re militari'' (late 4th century)
Modern
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External links
Roman Military Diplomas OnlineVindolanda Tablets Online
{{DEFAULTSORT:Auxiliaries (Roman Military)
Roman auxiliaries
The (, lit. "auxiliaries") were introduced as non-citizen troops attached to the citizen legions by Augustus after his reorganisation of the Imperial Roman army from 30 BC. By the 2nd century, the Auxilia contained the same number of inf ...
Military units and formations of the Roman Empire