The Bulgarian–Latin wars were a series of conflicts between the

Second Bulgarian Empire The Second Bulgarian Empire (; ) was a medieval Bulgarians, Bulgarian state that existed between 1185 and 1422. A successor to the First Bulgarian Empire, it reached the peak of its power under Tsars Kaloyan of Bulgaria, Kaloyan and Ivan Asen II ...

(1185–1396) and the

Latin Empire The Latin Empire, also referred to as the Latin Empire of Constantinople, was a feudal Crusader state founded by the leaders of the Fourth Crusade on lands captured from the Byzantine Empire. The Latin Empire was intended to replace the Byzantin ...

(1204–61). The wars affected the northern border of the Latin Empire throughout its existence. The initial expansionist ambitions of the Latin Empire were crushed only one year after its foundation after the

Battle of Adrianople The Battle of Adrianople also known as Battle of Hadrianopolis was fought between the Eastern Roman army led by the Roman emperor Valens and Gothic rebels (largely Thervings as well as Greutungs, non-Gothic Alans, and various local rebels) ...

in 1205, where its Emperor Baldwin I was captured and most of his knights perished. After that crucial defeat the Latin Empire had to defend itself against Bulgaria and the successor states of the Byzantine Empire, the Nicaean Empire in Asia Minor and the

Despotate of Epirus The Despotate of Epirus () was one of the Greek Rump state, successor states of the Byzantine Empire established in the aftermath of the Fourth Crusade in 1204 by a branch of the Angelos dynasty. It claimed to be the legitimate successor of the ...

in the Balkans. As a result of the conflicts the Bulgarian Empire expanded its territory taking control of most of the

Balkan Peninsula The Balkans ( , ), corresponding partially with the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throug ...

while the influence of the Latin Empire was reduced to Constantinople and a few towns and islands. With the elimination of the

Patriarchate of Constantinople The Ecumenical Patriarchate of Constantinople (, ; ; , "Roman Orthodox Patriarchate, Ecumenical Patriarchate of Istanbul") is one of the fifteen to seventeen autocephalous churches that together compose the Eastern Orthodox Church. It is headed ...

by the

Roman Catholic The Catholic Church (), also known as the Roman Catholic Church, is the largest Christian church, with 1.27 to 1.41 billion baptized Catholics worldwide as of 2025. It is among the world's oldest and largest international institut ...

Crusaders, Bulgaria became the centre of Orthodox

Christianity Christianity is an Abrahamic monotheistic religion, which states that Jesus in Christianity, Jesus is the Son of God (Christianity), Son of God and Resurrection of Jesus, rose from the dead after his Crucifixion of Jesus, crucifixion, whose ...

Foundation of the Latin Empire

On 13 April 1204 the knights of the

Fourth Crusade The Fourth Crusade (1202–1204) was a Latin Christian armed expedition called by Pope Innocent III. The stated intent of the expedition was to recapture the Muslim-controlled city of Jerusalem, by first defeating the powerful Egyptian Ayyubid S ...

seized the capital of the Byzantine Empire (Eastern Roman Empire),

Constantinople Constantinople (#Names of Constantinople, see other names) was a historical city located on the Bosporus that served as the capital of the Roman Empire, Roman, Byzantine Empire, Byzantine, Latin Empire, Latin, and Ottoman Empire, Ottoman empire ...

, and replaced the ancient

Byzantine Empire The Byzantine Empire, also known as the Eastern Roman Empire, was the continuation of the Roman Empire centred on Constantinople during late antiquity and the Middle Ages. Having survived History of the Roman Empire, the events that caused the ...

with a new

Crusader state The Crusader states, or Outremer, were four Catholic polities established in the Levant region and southeastern Anatolia from 1098 to 1291. Following the principles of feudalism, the foundation for these polities was laid by the First Crusade ...

, the

. Their leader Count Baldwin of Flanders was crowned

Emperor The word ''emperor'' (from , via ) can mean the male ruler of an empire. ''Empress'', the female equivalent, may indicate an emperor's wife (empress consort), mother/grandmother (empress dowager/grand empress dowager), or a woman who rules ...

in the

Hagia Sophia Hagia Sophia (; ; ; ; ), officially the Hagia Sophia Grand Mosque (; ), is a mosque and former Church (building), church serving as a major cultural and historical site in Istanbul, Turkey. The last of three church buildings to be successively ...

as Baldwin I. According to the '' Partitio Romaniae'' he received a quarter of the Empire and the rest was divided between the Venetians and the

Crusaders The Crusades were a series of religious wars initiated, supported, and at times directed by the Papacy during the Middle Ages. The most prominent of these were the campaigns to the Holy Land aimed at reclaiming Jerusalem and its surrounding ...

. The Emperor received the lands in

Asia Minor Anatolia (), also known as Asia Minor, is a peninsula in West Asia that makes up the majority of the land area of Turkey. It is the westernmost protrusion of Asia and is geographically bounded by the Mediterranean Sea to the south, the Aegean ...

as well as Constantinople and a thin strip along the

Black Sea The Black Sea is a marginal sea, marginal Mediterranean sea (oceanography), mediterranean sea lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bound ...

coast and a few other towns in the

Balkans The Balkans ( , ), corresponding partially with the Balkan Peninsula, is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains that stretch throug ...

. The Venetians took the most fertile part of Byzantine

Thrace Thrace (, ; ; ; ) is a geographical and historical region in Southeast Europe roughly corresponding to the province of Thrace in the Roman Empire. Bounded by the Balkan Mountains to the north, the Aegean Sea to the south, and the Black Se ...

including

Adrianople Edirne (; ), historically known as Orestias, Adrianople, is a city in Turkey, in the northwestern part of the Edirne Province, province of Edirne in Eastern Thrace. Situated from the Greek and from the Bulgarian borders, Edirne was the second c ...

(Odrin), Rodosto, Arkadiopolis, most of the

Peloponnese The Peloponnese ( ), Peloponnesus ( ; , ) or Morea (; ) is a peninsula and geographic region in Southern Greece, and the southernmost region of the Balkans. It is connected to the central part of the country by the Isthmus of Corinth land bridg ...

, parts of

Epirus Epirus () is a Region#Geographical regions, geographical and historical region, historical region in southeastern Europe, now shared between Greece and Albania. It lies between the Pindus Mountains and the Ionian Sea, stretching from the Bay ...

and

Thessaly Thessaly ( ; ; ancient Aeolic Greek#Thessalian, Thessalian: , ) is a traditional geographic regions of Greece, geographic and modern administrative regions of Greece, administrative region of Greece, comprising most of the ancient Thessaly, a ...

as well as many islands. Their Doge took the title ''quartae partis et dimidiae totius imperii Romaniae dominator'' or "Lord of a quarter and a half part of the whole Roman Empire". The Crusaders received the other lands of the former Byzantine Empire and created the Kingdom of Thessalonica with Boniface of Montferrat selected for King.Gerland, Е. ''Geschichte des lateinischen Kaiserreiches von Konstantinopel''. 1. Teil: ''Geschichte des Kaisers Balduin I und Heinrich''. Homburg v. d. Höhe 1905. p. 29-30

Bulgarian intervention

In 1204, the

captured

, capital of the

, and created the Latin Empire, electing as emperor Baldwin I of Flanders. Although the

Bulgarians Bulgarians (, ) are a nation and South Slavs, South Slavic ethnic group native to Bulgaria and its neighbouring region, who share a common Bulgarian ancestry, culture, history and language. They form the majority of the population in Bulgaria, ...

had offered the crusaders an alliance against the Byzantine Empire, their offer had been spurned, and the Latin Empire expressed the intention of conquering all the lands of the former Byzantine Empire, including the territories ruled by

Kaloyan Kaloyan or Kalojan, also known as Ivan I, Ioannitsa or Johannitsa (; 1170 – October 1207), the Roman Slayer, was emperor or tsar of Bulgaria from 1196 to 1207. He was the younger brother of Theodor and Asen, who led the anti-Byzantine upr ...

, the Bulgarian emperor. The impending conflict was precipitated by the Byzantine aristocracy in

, which rebelled against Latin rule in 1205 and called on Bulgarians for help, offering the Bulgarians its submission.

Kaloyan's campaigns

As the Latin Emperor Baldwin I began to subdue rebel cities and besieged Adrianople, in the words of the Crusader chronicler Villehardouin, "Johannizza, King of

Wallachia Wallachia or Walachia (; ; : , : ) is a historical and geographical region of modern-day Romania. It is situated north of the Lower Danube and south of the Southern Carpathians. Wallachia was traditionally divided into two sections, Munteni ...

, was coming to succour Adrianople with a very great host; for he brought with him Wallachians and Bulgarians, and full fourteen thousand Comans who had never been baptised" (Villehardouin, 92). On April 14, 1205, the

Cumans The Cumans or Kumans were a Turkic people, Turkic nomadic people from Central Asia comprising the western branch of the Cumania, Cuman–Kipchak confederation who spoke the Cuman language. They are referred to as Polovtsians (''Polovtsy'') in Ru ...

(allied to Kaloyan) managed to draw the pursuing heavy cavalry of the Latin Empire into an ambush in the marshes north of Adrianople, and the

and Bulgarians inflicted a crushing defeat on the crusader army. Emperor Baldwin I was captured, Count Louis I of Blois was killed, and the Venetian Doge Enrico Dandolo led the surviving portions of the crusader army into a hasty retreat back to Constantinople, during the course of which he died of exhaustion. (Baldwin was imprisoned in the Bulgarian capital Tărnovo until he died or was executed later in 1205.) During the course of 1205, Kaloyan captured

Serres Serres ( ) is a city in Macedonia, Greece, capital of the Serres regional unit and second largest city in the region of Central Macedonia, after Thessaloniki. Serres is one of the administrative and economic centers of Northern Greece. The c ...

and Philippopolis (

Plovdiv Plovdiv (, ) is the List of cities and towns in Bulgaria, second-largest city in Bulgaria, 144 km (93 miles) southeast of the capital Sofia. It had a population of 490,983 and 675,000 in the greater metropolitan area. Plovdiv is a cultural hub ...

), overrunning much of the territory of the Latin Empire in Thrace and

Macedon Macedonia ( ; , ), also called Macedon ( ), was an ancient kingdom on the periphery of Archaic and Classical Greece, which later became the dominant state of Hellenistic Greece. The kingdom was founded and initially ruled by the royal ...

ia. However, the progress of the Bulgarians eventually was interrupted by the assassination of their emperor Kaloyan. On January 31, 1206 the Bulgarians defeated the Latins again in Thrace, and later proceeded to capture Didymoteikhon. They repeatedly ravaged Thrace, including the important cities of Herakleia and Tzouroulos, and prompting the evacuation of other cities, such as Rodosto (

Tekirdağ Tekirdağ () is a city in northwestern Turkey. It is located on the north coast of the Sea of Marmara, in the region of East Thrace. The city forms the urban part of the Süleymanpaşa district, with a population of 186,421 in 2022. Tekirdağ ...

). Whereas in the past the Bulgarian emperor,

, had limited his oppression to the aristocracy, his later campaigns included wholesale transfer of populations from the captured cities to distant regions in Bulgaria. The Bulgarians besieged Adrianople twice, but failed to take the city because of the withdrawal of their Cuman cavalry, and the determined advance of the new Latin emperor, Baldwin I's brother Henry of Flanders. In 1207 the Bulgarians concluded an anti-Latin alliance with Theodore I Laskaris of the

Empire of Nicaea The Empire of Nicaea (), also known as the Nicene Empire, was the largest of the three Byzantine Greeks, Byzantine Greek''A Short history of Greece from early times to 1964'' by Walter Abel Heurtley, W. A. Heurtley, H. C. Darby, C. W. Crawley, C ...

. In the same year, the Bulgarians killed Boniface of Montferrat (September 4, 1207), the Latin ruler of the Kingdom of

Thessalonica Thessaloniki (; ), also known as Thessalonica (), Saloniki, Salonika, or Salonica (), is the second-largest city in Greece (with slightly over one million inhabitants in its metropolitan area) and the capital city, capital of the geographic reg ...

. Seeking to take advantage of that situation, Kaloyan advanced on the city and besieged it with a large force, but was murdered by his own Cuman commander Manastăr at the beginning of October 1207. In keeping with tradition, the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

citizens of

attributed the slaying of Kaloyan to their patron, Saint Demetrios.

Peace

Kaloyan's successor Boril, his nephew, was not nearly as successful against the Latins. His policy against the Latin empire in Thrace continued with varying success. In 1208 Boril achieved a victory against the Latins in the battle of Beroia but was defeated by Henry of Flanders in the following engagement near Plovdiv the same year. Despite the defeat, Boril managed to retain his main forces and continued to campaign against the Latins, reaching in some daring actions the vicinity of Constantinople, a clear evidence of the positions he had regained in the Balkans. In 1210 a peace was concluded, when the Hungarians and Latin empire made an alliance.

Fall of the Latin Empire

By 1231 the Latin regency had finalized negotiations with

John of Brienne John of Brienne ( 1170 – 19–23 March 1237), also known as John I, was the king of Jerusalem from 1210 to 1225 and Latin emperor of Constantinople from 1229 to 1237. He was the youngest son of Erard II of Brienne, a wealthy nobleman in Cham ...

, the former king of Jerusalem, who was invited to step in as the guardian and co-emperor of Baldwin II at Constantinople. This action led to the breach of the alliance between Bulgaria and the Latin Empire, and the creation of an alternate alliance between Bulgaria and

. However, the Bulgarian emperor Ivan Asen II could not decide whether to support the Niceaen

Greeks Greeks or Hellenes (; , ) are an ethnic group and nation native to Greece, Greek Cypriots, Cyprus, Greeks in Albania, southern Albania, Greeks in Turkey#History, Anatolia, parts of Greeks in Italy, Italy and Egyptian Greeks, Egypt, and to a l ...

or the Latins, and no decisive action was taken. Eventually

Michael VIII Palaiologos Michael VIII Palaiologos or Palaeologus (; 1224 – 11 December 1282) reigned as Byzantine emperor from 1261 until his death in 1282, and previously as the co-emperor of the Empire of Nicaea from 1259 to 1261. Michael VIII was the founder of th ...

, the ruler of the Niceaen Empire captured Constantinople and restored the Byzantine Empire, bringing an end to the Latin Empire.

Bulgarian–Latin battles

Footnotes

References

* * * Vannier, J-F. Les premiers Paléologues (Etudes prosopographiques), 1989 * * Niketas Choniates, Nicetae Choniatae Historia, Bonn, 1835. * Magoulias, Harry J. (transl.). O City of Byzantium, Annals of Niketas Choniates, 1984, * Ansbert, ''

Historia de expeditione Friderici imperatoris The ''History of the Expedition of the Emperor Frederick'' (Latin: ''Historia de expeditione Friderici imperatoris'') is an anonymous Latin account of the campaign waged by Frederick I, Holy Roman Emperor, as part of the Third Crusade. It covers t ...

'', Monumenta Germaniae Historica, Scriptores, n.s. 5, 15-70. * Mauro Orbini, Il Regno di Slavi, Pesaro, 1601.