Latin word imperator derives from the stem of the verb imperare,
meaning ‘to order, to command’. It was originally employed as a
title roughly equivalent to commander under the Roman Republic. Later
it became a part of the titulature of the Roman Emperors as part of
their cognomen. The English word emperor derives from imperator via
Old French Empereür. The Roman emperors themselves generally based
their authority on multiple titles and positions, rather than
preferring any single title. Nevertheless, imperator was used
relatively consistently as an element of a Roman ruler's title
throughout the principate (derived from princeps, from which prince in
English is derived) and the dominate.
In Latin, the feminine form of imperator is imperatrix, denoting a
1 Imperatores in the ancient Roman Kingdom
2 Imperatores in the Roman Republic
Imperator as an imperial title
4 Post-Roman use
Imperatores in the ancient Roman Kingdom
Rome was ruled by kings, to be able to rule, the king had to
be invested with the full regal authority and power. So, after the
comitia curiata, held to elect the king, the king also had to be
conferred the imperium.
Imperatores in the Roman Republic
In Roman Republican literature and epigraphy, an imperator was a
magistrate with imperium. But also, mainly in the later Roman
Republic and during the late Republican civil wars, imperator was the
honorific title assumed by certain military commanders. After an
especially great victory, an army's troops in the field would proclaim
their commander imperator, an acclamation necessary for a general to
apply to the Senate for a triumph. After being acclaimed imperator,
the victorious general had a right to use the title after his name
until the time of his triumph, where he would relinquish the title as
well as his imperium.
Since a triumph was the goal of many politically ambitious Roman
commanders, Roman Republican history is full of cases where legions
were bribed to call their commander imperator. The title of imperator
was given in 90 BC to Lucius Julius Caesar, in 84 BC to Gnaeus
Pompeius Magnus, in 60 BC to Gaius Julius Caesar, relative of the
previously mentioned Lucius Julius Caesar, in 45 BC again to Gaius
Julius Caesar, in 44 BC to Marcus Iunius Brutus, and in 41 BC to
Lucius Antonius (younger brother and ally of the more famous Marcus
Antonius). In 15 AD
Germanicus was also imperator during the empire
(see below) of his adoptive father Tiberius.
Imperator as an imperial title
Augustus established the Roman Empire, the title imperator was
generally restricted to the emperor, though in the early years of the
empire it would occasionally be granted to a member of his family. As
a permanent title, imperator was used as a praenomen by the Roman
emperors and was taken on accession. After the reign of Tiberius, the
act of being proclaimed imperator was transformed into the act of
imperial accession. In fact, if a general was acclaimed by his troops
as imperator, it would be tantamount to a declaration of rebellion
against the ruling emperor. At first the term continued to be used in
the Republican sense as a victory title but attached to the de facto
monarch and head of state, rather than the actual military commander.
The title followed the emperor's name along with the number of times
he was acclaimed as such, for example IMP V ("imperator five times").
In time it became the title of the de facto monarch, pronounced upon
(and synonymous with) their assumption.
As a title imperator was generally translated into Greek as autokrator
("one who rules himself," also sometimes used as a translation for
Roman dictators.) This was necessarily imprecise as it lost the
Latin political thought contrasting imperium with other
forms of public authority. Nevertheless, this title (along with
sebastos for augustus) was used in Greek-language texts for Roman
emperors from the establishment of the empire.
In the east, the title continued to be used into the Byzantine period,
though to a lesser, and much more ceremonial, extent. In most
Byzantine writings, the Greek translation "Autokrator" is preferred,
but "Imperator" makes an appearance in Constantine IV's mid 7th
century mosaic in the Basilica of Sant'Apollinare in Classe, and on
various 9th century lead seals.
After the Roman empire collapsed in the West in the 5th century, Latin
continued to be used as the language of learning and diplomacy for
some centuries. The Roman emperors of this period (referred to by
modern historians as the Byzantine emperors) were referred to as
Latin texts, while the word basileus (king) was used in
After 800, the imperator was used (in conjunction with augustus) as a
Latin title in succession by the
Carolingian and German Holy
Roman Emperors until 1806 and by the Austrian Emperors until 1918.
In 1721, as part of his drive to both westernize the Russian Empire
and assert the monarchy's claim that it was the successor to the
Peter the Great
Peter the Great imported the
Latin word directly
into Russian and styled himself imperator (Императоръ). The
style remained the official one for all his successors down to the end
Russian Empire in 1917, though the Russian rulers continued to
be colloquially known as tsar (a word derived from "Caesar"), which
they had begun to use c. 1480 to likewise assert their contention to
be the heirs to the Byzantine state (see: Third Rome.) Reigning female
Russian rulers were styled imperatritsa.
Signature of King Edward VIII. The "R" and "I" after his name indicate
Rex ("king") and
Imperator ("emperor") respectively.
German East African Roupie, 1890. Coins of European Colonial Empires
were sometimes inscribed in Latin, such as this colonial coin
featuring Wilhelm II of Germany.
Napoleon famously adopted the title for himself and after the
Napoleonic wars, the number of emperors in Europe proliferated, but
Latin began to fall out of use for all but the most ceremonial
situations. Still, in those rare cases in which a European monarch's
Latin titles were used, imperator was used as a translation for
emperor. Famously, after assuming the title
Emperor of India, British
monarchs would follow their signatures with the initials RI, standing
for rex imperator ("king-emperor"). George VI of the United Kingdom
was the last European ruler to claim an imperial title; when he
Emperor of India in 1948, the last active use of the
title imperator in the West ceased. It was thereafter used only
historically, or as a
Latin translation for certain continuing titles
of non-European cultures, such as Japan.
The imperial title was also adopted by Jean-Bédel Bokassa, during his
reign as the emperor of the short-lived Central African Empire
The term imperatrix seems not to have been used in
Ancient Rome to
indicate the consort of an imperator or later of an Emperor. In the
early years of the
Roman Empire there was no standard title or
honorific for the Emperor's wife, even the "Augusta" honorific was
rather exceptionally granted, and not exclusively to wives of living
It is not clear when the feminine form of the
Latin term imperator
originated or was used for the first time. It usually indicates a
reigning monarch, and is thus used in the
Latin version of titles of
modern reigning Empresses.
Likewise, when Fortuna is qualified "imperatrix mundi" in the Carmina
Burana there's no implication of any type of consort — the term
describes (the Goddess or personified) Fortune "ruling the world".
In Christian context, Imperatrix became a laudatory address to the
Virgin Mary, in diverse forms at least since the Middle Ages — for
example, she is sometimes called "Imperatrix angelorum" ("regnant of
Imperator is the root of most Romance languages' word for emperor. It
is the root of the English word "emperor", which entered the language
via the French empereur, while related adjectives like "imperial" were
imported into English directly from Latin.
^ Rex.A Dictionary of Greek and Roman Antiquities, John Murray,
^ LacusCurtius • Roman Law — Auctor (Smith's Dictionary, 1875)
^ Rivero (2006).
^ Tacitus, The Annals 1.58
Combès, Robert (1966). Imperator : Recherches sur l’emploi et
la signification du titre d’
Imperator dans la
Paris: Presses universitaires de France; Publications de la Faculté
des Lettres et Sciences humaines de l’Université de Montpellier.
Archived from the original on 2010-12-30. 489 p.
Rivero, Pilar (2006).
Imperator Populi Romani: una aproximación al
poder republicano. Zaragoza: Institución Fernando el Católico.
514 p. (Biblioteca virtual at http://ifc.dpz.es).
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