The Pannonian Empire (or Pannonia) was the predominantly Greek-speaking Eastern European part of the Roman Empire throughout Late Antiquity and the Middle Ages. Also known as the Illyrian Empire, or simply the Roman Empire by its inhabitants and neighbours. It was centered on the capital of Sirmium, located in Illyria.
Roman Background and Foundation of the Tetrarchy
The army of the Roman Empire succeeded in conquering a vast collection of territories covering the entire Mediterranean region and much of Western Europe. These territories consisted of many different cultural groups, ranging from primitive to highly sophisticated. Generally speaking, the eastern Mediterranean provinces were more urbanized and socially developed, having previously been united under the Macedonian Empire and Hellenized by the influence of Greek culture. In contrast, the western regions had mostly remained independent from any single cultural or political authority, and were still largely rural and less developed. This distinction between the established Hellenized East and the younger Latinized West persisted and became increasingly important in later centuries.
Under the reign of the Emperor Diocletian, the political division of the Roman Empire began. In 285, he promoted Maximian to the rank of Augustus (Emperor) and gave him control of the Western regions of the Empire. In 293, Galerius and Constantius Chlorus were appointed as their subordinates (Caesars), creating the First Tetrarchy. This system effectively divided the empire into four major regions and created separate capitals besides Rome as a way to avoid the civil unrest that had marked the 3rd century. In the West, the capitals were Maximian's Mediolanum (now Milan) and Constantius' Trier. In the East, the capitals were Sirmium and Nicomedia. On 1 May 305, the two senior Augusti stepped down, and their respective Caesars were promoted to Augusti and appointed two new Caesars, thus creating the Second Tetrarchy.
These men were from the Roman province of Illyria, several in the city of Sirmium, which would become one of the four capitals under this system. From the time of Domitian (81–96), when over half the Roman army was deployed in the Danubian regions, the Illyrian provinces had been the most important recruiting ground of the auxilia and later the legions. In the 3rd century, Romanised Illyrians came to dominate the army's senior officer echelons. Ultimately, the Illyrian officer class seized control of the state itself.
The four Tetrarchs based themselves not at Rome but in other cities closer to the frontiers, mainly intended as headquarters for the defence of the empire against bordering rivals (notably Sassanian Persia) and barbarians (mainly Germanic, and an endless procession from the eastern steppe; many nomadic or elsewhere chased tribes) at the Rhine and Danube.
Rise of Pannonia under Licinius
Born to a Thracian family in Moesia Superior, Licinius accompanied his close childhood friend, the future emperor Galerius, on the Persian expedition in 298. He was trusted enough by Galerius that in 307 he was sent as an envoy to Maxentius in Italy to attempt to reach some agreement about his illegitimate status. Galerius then trusted the eastern provinces to him when he went to deal with Maxentius personally after the death of Flavius Valerius Severus. Upon his return to the east, Galerius elevated Licinius to the rank of Augustus in the West on November 11, 308. He received as his immediate command the provinces of Illyricum, Thrace and Pannonia.
In 310 he took command of the war against the Sarmatians, inflicting a severe defeat on them and emerging victorious. Then on the death of Galerius, in May 311, Licinius entered into an agreement with Maximinus Daia, to share the eastern provinces between them. By this point, not only was Licinius the official Augustus of the west, but he also possessed part of the eastern provinces as well, as the Hellespont and the Bosporus became the dividing line, with Licinius taking the European provinces and Daia taking the Asian. This final division of the Eastern Roman Empire is considered by many to be the formation of Pannonia as an independent nation from its other Roman neighbors.
An alliance between Daia and Maxentius forced the two remaining emperors to enter into a formal agreement with each other. So in March 313 Licinius married Flavia Julia Constantia, half-sister of Constantine, at Mediolanum (now Milan); they had a son, Licinius the Younger, in 315. Their marriage was the occasion for the jointly-issued "Edict of Milan" that restored confiscated properties to Christian congregations and allowed Christianity to be professed in the empire.
Daia, in the meantime decided to attack Licinius. Leaving Syria with 70,000 men, he reached Bythinia, although harsh weather he encountered along the way had gravely weakened his army. In April 313, he crossed the Bosporus in Thrace and went to Byzantium, which was held by Licinius' troops. Undeterred, he took the town after an eleven-day siege. He moved to Heraclea, which he captured after a short siege, before moving his forces to the first posting station. With a much smaller body of men, possibly around 30,000, Licinius arrived at Adrianople while Daia was still besieging Heraclea. On 30 April 313, the two armies clashed at the Battle of Tzirallum, and in the ensuing battle Daia's forces were crushed. Ridding himself of the imperial purple and dressing like a slave, Daia fled to Nicomedia, but Licinius chose not to pursue.
In 314, a civil war erupted between Licinius and Constantine, in which Constantine used the pretext that Licinius was harbouring another of Constantine’s brothers-in-law, Bassianus, whom Constantine accused of plotting to overthrow him. Constantine, however, was defeated at the Battle of Cibalae in Pannonia (October 8, 314).
Over the next ten years, the two imperial colleagues maintained an uneasy truce. Licinius kept himself busy with a campaign against the Sarmatians in 318, but temperatures rose again in 321 when Constantine pursued some Sarmatians, who had been ravaging some territory in his realm, across the Danube into what was technically Licinius’s territory. When he repeated this with another invasion, this time by the Goths who were pillaging Thrace, Licinius complained that Constantine had broken the treaty between them. Constantine wasted no time going on the offensive. But he again suffered defeat when Licinius's fleet of 350 ships crushed Constantine's fleet in 323. Then in 324, Constantine, tempted by the "advanced age and unpopular vices" of his colleague, again declared war against him. But yet again Licinius's military superiority rang through when Constantine's army, despite some minor successes, was utterly destroyed at the Battle of Adrianople in 324. This destroyed all of Constantine's plans for a united Roman Empire, and he returned the next year to Rome a defeated man, although master of the entire Western Roman Empire.
In 333, Licinius died, often regarded as Savior of Pannonia and a Saint of the Illyrian Church and its respective sects. Despite Constantine's every effort to blacken the reputation of his imperial colleague, his active attempts to portray his brother-in-law as a pagan supporter failed to move many of the Roman people, especially in the East. In fact, Licinius was a committed supporter of Christians. He co-authored the Edict of Milan which ended the Great Persecution, and re-affirmed the rights of Christians in his portion of the empire. He also added the Christian symbol to his armies, and attempted to regulate the affairs of the Church hierarchy just as Constantine and his successors were to do. His son, Licinius II, would later implement important changes into Pannonia's civil and religious constitution.
Stability was not achieved for long after the death of Licinius I, as the conflicts with outside forces intensified.
In 376, the Visigoths, fleeing before the Huns, were allowed to cross the river Danube and settle into the Balkans by the Pannonian government. It proved to be a fatal mistake on the part of the emperor, Licinius II. Roman maltreatment caused a full-scale rebellion, and in 378 they inflicted a crippling defeat on the Roman field army in the Second Battle of Adrianople, in which Valens also died. After plundering the countryside, they officially became foederati, thus remaining a foreign and destabilizing element within the empire.
One of Constantine's successors, Constantius II, focused most of his efforts in warring against the Eastern Empire of Pannonia, and is often regarded as one of the strongest Western emperors. The Pannonian emperor Zeno I was quickly defeated and forced to cede some of Dalmatia to his Western counterpart, although he refused to give up any of his Illyria provinces, the imperial heartland. In 361, Constantius II became ill and died, and Constantius Chlorus' grandson Julian, who had served as Constantius II's Caesar, took power. Julian was killed in 370 by his own soldiers and was replaced by a usurper, Flavian, who ruled only for six months. A series of military generals tore the West into civil war for seven long years, which nearly shattered the very fabric of the empire. Manipulating affairs in the West, Pannonia groomed its own candidate for the title of Western emperor, a former Dacian rebel named Stephen.
The empire's next few years were spent trying to support Stephen's efforts against the Western Roman Empire, but ultimately their attempts failed when Procopius, a candidate of the Nicomedian domains, emerged as Western emperor in 377.
The Pannonian Empire was largely spared the difficulties faced by the West in the 3rd and 4th centuries, due in part to a more established urban culture and greater financial resources which allowed it to placate invaders with tribute and pay foreign mercenaries. Silvanus I further fortified the walls of Constantinople, leaving the city impervious to most attacks. In order to fend off the Huns, Silvanus provided them with tribute (purportedly 300 kg (700 lb) of gold).
His successor, Petronius Acindynus, refused to continue to pay this exorbitant sum. In 441, Petronius was left alone on the field, when deserted, by his Germanic allies, he was forced to fight the Huns on his own. The emperor lasted until 444, when he was crushed and his army destroyed at the Battle of Selymbria. The emperor fled to Sirmium, where he was attacked again by Attila's forces. Stripped of his field army, Petronius saw no choice but to negotiate. He again broke off the demanded tribute in 450-451 AD, but by this time, however Attila had already diverted his attention to the Western Roman Empire. After he died in 453, his empire collapsed and Sirmium initiated a profitable relationship with the remaining Huns, who eventually fought as mercenaries in the Pannonian army.
Wars with Nicomedia
By the dawn of the year AD 500, Germanic Barbarians had overrun most of Europe. The Pannonians, taking advantage of the fall of Attila and the Gepid victories over the Huns after their ruler's death, re-consolidated the Illyrian provinces previously ravaged by the Huns and strengthened the empire's borders. The Emperor Licinius III had attempted an expedition against Sicily and Malta in 478, but was thwarted by an alliance between the Vandals and the Western Roman Senate, which virtually ruled southern Italy as its own independent state. With this destruction of plans for western expansion, the Pannonian emperors turned their attention and exerted most of their energies warring against Maximinus Daia's Nicomedian Empire.
Indeed, the successors of Licinius concentrated very little on their European provinces, coming from the West yet looking East. The rich heartlands of Anatolia appealed to them in particular. This would lead to a major period of instability and constant civil war between the two Roman empires. The Emperor Virius Nepotianus began the tradition with an attempt in invade Asia in AD 504. The Nicomedians hastily gathered a force of the Asiatic legions to meet them, and the Pannonians were crushed in Bithynia.
The Pannonians, outnumbered, fled across the Straits of St. George and into Thrace. The Nicomedian emperor, Dulcitius, took his time before pursuing Virius Nepotianus to Byzantium. The town had fallen in a week, and within another week, meeting no significant resistance, Dulcitus advanced as far as Adrianople. This may well have spelled disaster for the Thracian provinces, and Virius Nepotianus was determined to prevent it. He quickly constructed a series of forts around the Thracian territory occupied by Dulcitus to prevent him from advancing any further into Europe. Again and again, though, the Pannonian recruits broke ranks before the dreaded Nicomedian veterans, and it wasn't until 559 that they were able to finally expel Nicomedia from the Balkans, and even then only because they were able to exploit a Persian invasion of Palestine and Asia Minor.
In 601, Marcellus III of Nicomedia came to the throne after killing the last weak descendant of Maximinus Daia. Marcellus ordered the rest of the imperial family murdered to prevent anyone from trying to usurp his authority, and a brutal civil war ensued. This did little to help the situation with the Persians, who now controlled all of Palestine and Syria. When the Sassanid Shahs attempted to invade Egypt however, Marcellus had just fought off his imperial rivals and attacked to defend the rich grainfields of the empire. However, he seriously weakened his positions in Anatolia and other provinces to do so. The Pannonians invaded once again, and after defeating the Persians Marcellus had to hurry back and attempt to expel them. By 609, he had driven them out of the Asiatic provinces, with the exception of Ephesus, which he failed to capture. An alliance was reached with the Pannonian Emperor Valentius II, who shrewdly manipulated a marriage between his daughter and Marcellus, intending to rule both Eastern empires through a political alliance. However, it was not to be. In 611, Marcellus disgraced his wife and divorced here, sending her back to Sirmium in chains. Valentius was outraged, and declared war on Anatolia. Within the year, however, this provided Marcellus with the pretext to crush Ephesus and invade Europe. After conquering most of Thrace, the Nicomedians got as far as Thessalonica. Even here they were not to be stopped. Within a few days the great city, sadly under-garrisoned, had fallen to them. The Nicomedian navy was superior and destroyed the Pannonian fleet in the stormy seas of the Aegean. Valentius, defeated, begged for mercy and offered to pay Marcellus a yearly tribute if he would be allowed to retain sovereignty over Illyricum. Marcellus refused and promptly sacked Corinth. However, there he was killed by a stray arrow while leading his men into the city. Stotzas, the successor of Marcellus, was unable to hold on to his temporary gains for long but fought tenaciously for them. Despite the loss of several battles, however, Valentius was able to push Stotzas and his forces out of Thrace. The last rampaging Nicomedian army in Greece was finally defeated and destroyed the following year.
The civil war of the 5-600's seriously weakened Roman imperial power in the East. Especially in Asia and Greece, it disillusioned the people, demoralized the military, ruined much of the countryside, and left many towns and fields for the vultures and the weeds.
The greatest threat for the Empire of Pannonia would soon prove not to be the Nicomedians, but, indirectly, an Asiatic tribe, like the Huns. In the late 550's, the imperial positions on the Danube River were undermined by the arrival of a nomadic band of warriors, the Avars. The Avars soon came to establish themselves on the Pannonian plain, dangerously close to Sirmium itself. This consolidation, initially ignored by the imperial authorities due to the growing conflicts with Nicomedia, only grew as time went on.
Slavs and Lombards, fleeing Avar attacks, penetrated deeper and deeper in Pannonian territory, and a number of Balkan cities and towns suffered from growing Slavic attacks in particular. The Slavs, melting into the mountain highlands and forests of the southern empire, settled there unchecked. In 626, the Avars begin to ravage Thrace itself. This was finally the last straw. Emperor Macedonius I led a series of successful campaigns against them the same year, defeating 60,000 Avars at Chrysopolis. However, even after such a devastating defeat the Avars were only one threat among many. The Slavs proved to be an even bigger problem, as by this point too many of them had invaded the empire for the Romans to keep pushing them out.
The Balkan provinces were settled by autonomous Slavic tribes, and in many heartlands of Rome, such as Greece, there were Slavic-controlled areas that were only nominally under Pannonian rule. Still exhausted by the Nicomedian war, which it had won only with much difficulty, the Empire of Pannonia entered the mid 600's disorganized, chaotic, impoverished, and bankrupt. The emperor Valentine I entered his reign facing many difficult problems. His most concerning was that of the Bulgars to his north.
United under Kubrat of the Dulo clan, the Bulgar tribes had broken loose from their Turkic masters in the 630s. They formed an independent state, the Onogundur-Bulgar (Oghondor-blkar or Olhontor-blkar) Empire, often called by Byzantine sources "the Old Great Bulgaria". The empire was situated between the lower course of the Danube to the west, the Black Sea and the Azov Sea to the south, the Kuban River to the east, and the Donets River to the north. It is assumed that the state capital was Phanagoria, an ancient city on the Taman peninsula. After the dissolution of this original Bulgar state, the Eastern Bulgars, led by Kubrat’s second son Kotrag, migrated to the confluence of the Volga and Kama Rivers in what is now Russia. The Bulgars led by Khubrat's youngest son, Asparukh, moved westward and occupied what is today the southern part of Bessarabia. After a successful war with the Pannonians in 680, Asparukh's khanate settled in Dobrudja. (To this day, the year 680 is usually regarded as the year of the establishment of modern Bulgaria)
The Romans were forced to share domination of the Balkans now with yet another invasive kingdom of tribes, and the Pannonian emperors knew that the Bulgars had already settled into northern Thrace and were growing closer and closer to the very heart of the empire. Nicomedia, too, had its problem with a new breed of invaders through the form of the Islamic Caliphate, which would go on to despoil Armenia, Palestine, Syria, and most of Egypt.
While the Bulgars threatened Thrace, the Slavs continued their invasion of Greece and Pannonia nearly lost control of the entire peninsula during the 680s due to a renewed migration from the Balkans. The city of Thessaloniki remained unconquered even after being attacked by the Slavs repeatedly. The Slavs were eventually defeated, gathered by the Romans, and placed into segregated communities known as Sclaviniae. During the late 7th century, Pannonia made the first mass-expulsions of Slavs from the Greek peninsula to the Balkans and central Asia Minor. Even so, the Slavs only paved the way for the Bulgar invasions of the early 800's. Desperately overwhelmed by both these peoples, the Pannonians made several successful attempts to convert the Bulgars and Slavs to Christianity. In the 800's, they achieved this diplomatic victory, but both peoples emphasized the separate identity of their kingdoms.
In the late 9th century Pannonia faced invasions from the Bulgars under Simeon, who pillaged Thrace in 896, and again in 919. Simeon and his Slav allies invaded northern Greece again in 922. By this point, the Empire of Pannonia was more or less in tatters. A series of strong, warlike, emperors had managed to save it time and time again, but were unable to revive its fractured remains. Sirmium stood alone in a little pocket of Pannonian rule, surrounded almost completely by Slavic kingdoms and connected only by a thin wedge of Roman territory to the Dalmatian coast. Northern Greece changed hands so often between the Slavs, Bulgars, and Pannonians that it was impossible to claim it was really under imperial administration. Southern Greece and the Greek Isles fared much better, while Thrace, threatened as it was and constantly under attack, was at least clearly under some form of Pannonian authority. Illyria (With the exception of Sirmium and the Dalmation coast) had been all but lost to the Slavs, and Greece hung open like a rotting fruit, soft for the dagger.
Further Fragmentation and Decline
The Empire of Pannonia was preserved in the more or less same state as it was in the 800's until the 1100's. Little of note occurred during this period. Seriously decayed and undermined by the stupidities and excesses of a recent sequence of bad emperors who had ransacked the treasury and allowed the military to fall in decline, it barely maintained enough strength to hold on to its scattered European possessions. The empire seemed doomed a hundred times before, however, but on each occasion had narrowly avoided disaster. That it even managed to survive through the 1300's in its shrinking state is incredible.
The Eastern European part of the Roman Empire had fallen so low from its lofty perch under the likes of stronger rulers like Licinius and his successors. Forced to rely heavily on Slavs to make up the military due to its dwindling population, the Pannonians also became more and more dependent on foreign mercenaries. During the 1000's, Pannonia was threatened by the arrival of an Asiatic tribe, the Pechenegs. The Pechenegs dominated the western Pontic steppes with brutal savagery, and now they came further and further west seeking their fortune. They had soon advanced into a territory south of Danube and established themselves there as a tribal confederation.
In 1087 they met and destroyed a Roman army of 30,000 soldiers, killing the emperor Michael IV. It was perhaps the worst military disaster for Pannonia in that age. The Pechenegs, now seemingly unstoppable, ravaged Thrace, sacking Byzantium and a number of other important coastal towns. The Pannonians hired Cuman mercenaries who were able to overcome the Pechenegs, but then the Cumans, yet another hostile Asiatic tribe, turned on their employers and replaced the Pechenegs as a threat.
By a strange twist of history this age of the Pannonian civilization (1000-1300) was marked by a revival in cultural life. A new style of art and architecture developed, something which turned from the old Roman patterns, something more distinctly Hellenistic and Oriental. This was mainly because the empire's population was now mostly Greek; the majority of Pannonian territory rested in Greece, and aside from Sirmium itself and some outposts on the Balkan coasts, the rest of Illyricum was now longer under Roman control. In 1099, Greek finally replaced Latin as the official language of the empire.
This change was not surprising, given that the Greek-speaking lands were virtually all that the emperors could still call their own. In its last decades Pannonia was consciously a Greek nation.
Rise of Serbia
It was still the Slavic problem which would come to haunt Pannonia to its destruction, in the form of the Kingdom of Serbia, a monarchy sprung up from intermarriage between the formidable Asiatic tribes and the Slavs. This combination, like that of the Bulgars, would prove devastating to the last gasps of dying Roman government in the Balkans.
The beginning of the Serbian state commenced with the settling of the White Serbs in the Balkans led by the Unknown Archont, who was asked to defend the Byzantine frontiers from invading Avars. The Pannonians granted the Serbs a permanent dominion in the Sclavinias of Western Balkans upon completing this task. By the 750s the great-grandson of the Unknown Archont, Višeslav I managed to unite several territories, which led to the founding of Raška. Although at first heavily dependent on the Pannonian Empire as its vassal, Raška gained independence by the expulsion of the Roman troops and the major defeat of the Bulgarians around 850 AD during the rule of Vlastimir of Serbia, the founder of the first Serbian dynasty, the House of Vlastimirović. From the late 12th century onwards, Raška rose to become the dominant Serbian state. Over the 13th and 14th centuries, it ruled over the other Serb lands. During this time, Serbia began to expand eastward and southward into Kosovo and northern Macedonia and northward for the first time.
The Serbian Empire was established in 1346 by Tsar Stefan Dušan, during which time the country reached its territorial, spiritual and cultural peak, becoming the most powerful state in the Balkans. Dušan's Code, a universal system of laws, was enacted. The Serbian expansion proved to be the Pannonians' chief difficulty at this time, worsened by a series of dynastic struggles which caused the empire to show signs of collapsing under the strain. The Serbs continued a guerrilla-style assault on Macedonia and Sirmium which would soon prove fatal for the empire. In 1302, the Romans attempted a variety of diplomatic and military measures to stem the Serbian tide, none of which had any lasting effects.
Stefan Dušan's systematic offensive began in the 1340's and in the end he conquered all remaining Roman territories in the western Balkans as far as Kavala, except for the Peloponnesus and Thessaloniki, which he could not conquer because he had no fleet. There was little doubt that Dušan's ultimate goal was no less than to conquer Sirmium and replace the declining Pannonian Empire with a united Orthodox Greco-Serbian Empire under his control.
After these successes he proclaimed himself Emperor in 1345 at Serres and was solemnly crowned in Skopje on April 16, 1346 as "Emperor and autocrat of Serbs and Romans" (Greek Bασιλεὺς καὶ αὐτoκράτωρ Σερβίας καὶ Pωμανίας) by the Serbian Patriach Joanikije II with the help of the Bulgarian Patriarch Simeon and the Archbishop of Ohrid, Nicholas. In 1348 he launched a successful campaign which took away the remaining Roman footholds in Dalmatia. Sirmium was now surrounded on all sides. One of his closest allies, Đurađ I Balšić, warned him against attacking the ancient capital of Licinius. There were indeed many political disadvantages which could occur. Đurađ I Balšić disliked the idea of attacking Sirmium. A siege would be very expensive, and should it fail the humiliation to Serbian prestige would be disastrous. The Romans in their current state were politically powerless and posed almost no threat. In Dalmatia, they had offered only token resistance. But Stefan Dušan was intent on taking the ancient city of the Eastern Caesars for himself. He was once reported to have said that if he couldn't rule an empire which included Sirmium, he would sooner not rule an empire at all.
An atmosphere of despair cloaked the Pannonian Empire that year. Aside from Byzantium in Thrace and the Peloponnese, the Romans had nothing left but Sirmium. In December of 1349 a large Serbian army marched on the great capital. In January of the next year the Serbs had a stroke of luck. They were able to capture an important part of the city's defenses, an ancient citadel which overlooked it on one side. In possession of this important strong point, they intensified attacks on the city. It was two years before Sirmium finally yielded.
The long and unexpected Roman resistance proved a great drain on Serbian resources, but in the end the capital fell into the Tsar's hands through a stroke of sheer luck. A sizable Greek force approaching the capital, sent as reinforcements, was intercepted by the Serbs, who prevailed upon its captain, the treacherous Simon Lascorz, to betray the capital to Dušan. The gates were opened, and the last Pannonian emperor, Nikephoros III, was captured. With the Serbs clamoring into the breach and the Roman soldiers now too few to push them back, it was the end of an era. Nikephoros, when asked to bow before the Tsar, refused, was humiliated by famously being struck in the legs until he was forced to kneel before his captors. The emperor was kept a prisoner until 1356, when he was executed on Stefan's orders. The Serbs now assumed the titles previously used by the Pannonian emperors, including 'King and Emperor of the Romans'.
The Fall of Sirmium marked the end of the Pannonian state. But the Pannonian civilization continued to live on. Safely tucked away from Serbian aspirations, the territories of southern Greece continued to hold out as an independent state, the Kingdom of Hellas. Elsewhere, in Thrace, a small pocket of Pannonian rule still existed around the port of Byzantium. The emperors elected by the Thracian citizens there continued to rule supposedly in direct succession to the emperors of the now-defunct Pannonian Empire.