The dawn of Greco-roman civilisation in Balkans (Part A) : The destructive raids of Avar nomads

Starting in the 2nd century BC the rising Roman Empire began annexing the Balkan area, transforming it into one of the Empire's most prosperous and stable regions. To this day, the Roman legacy is clearly visible in the numerous monuments and artifacts scattered throughout the Balkans, and most importantly in the Latin-based languages used by almost 25 million people in the area (the Balkan Romance languages). However, the Roman influence failed to dissolve Greek culture, which maintained a predominant status in the Eastern half of the Empire, and continued to be strong in the southern half of the Balkans. Beginning in the 3rd century AD, Rome's frontiers in the Balkans were weakened because of internal political and economic disorders. During this time, the Balkans, especially Illyricum, grew to greater importance. It became one of the Empire's four prefectures, and many warriors, administrators and emperors arose from the region. Many rulers built their residences in the region. Though the situation had stabilized temporarily by the time of Constantine, waves of non-Roman peoples, most prominently the Thervings, Greuthungs and Huns, began to cross into the territory, first as refugees with imperial permission to take shelter from their foes the Huns, then later as invaders. Turning on their hosts after decades of servitude and simmering hostility, Thervingi under Fritigern and later Visigoths under Alaric I eventually conquered and laid waste the entire Balkan region before moving westward to invade Italy itself. By the end of the Empire the region had become a conduit for invaders to move westward, as well as the scene of treaties and complex political maneuvers by Romans, Goths and Huns, all seeking the best advantage for their peoples amid the shifting and disorderly final decades of Roman imperial power.

The Byzantine Empire was the Greek-speaking, Eastern Roman Empire during the Middle Ages, centered at its capital in Constantinople. During most of its history it controlled provinces in the Balkans and Asia Minor. The Eastern Roman Emperor Justinian for a time retook and restored much of the territory once held by the unified Roman Empire, from Spain and Italy, to Anatolia. Its expert military and diplomatic power ensured inadvertently that Western Europe remained safe from many of the more devastating invasions from eastern peoples, at a time when the still new and fragile Western Christian kingdoms might have had difficulty containing it. The magnitude of influence and contribution the Byzantine Empire made to Europe and Christendom has only begun to be recognised recently. Its rich historiographical tradition preserved ancient knowledge upon which splendid art, architecture, literature and technological achievements were built. This is embodied in the Byzantine version of Christianity, which spread Orthodoxy and eventually led to the creation of the so-called "Byzantine commonwealth" throughout Eastern Europe. Early Byzantine missionary work spread Orthodox Christianity to various Slavic peoples, amongst whom it still is a predominant religion.

Coinciding with the decline of the Roman Empire, many "barbarian" tribes passed through the Balkans, most of whom did not leave any lasting state. During these "Dark Ages", Eastern Europe, like Western Europe, regressed culturally and economically, although enclaves of prosperity and culture persisted along the coastal towns of the Adriatic and the major Greek cities in the south. The local Romans and Romanized remnants of the Iron Age populace of the Balkans began their assimilation into mainly the Slavs and Greeks, however, notable Latin-speaking communities are known to have survived. In literature, these Romance-speakers are known as "Vlachs". In Dacia, Roman colonists and Romanized Dacians retreated in the Carpathian Mountains of Transylvania after the Roman withdrawal. Archaeological evidence indicate a Romanized population in Transylvania by at least the 8th century. By the 7th and 8th centuries, the Roman Empire existed only south of the Danube River in the form of the Byzantine Empire, with its capital at Constantinople. In this ethnically diverse closing area of the Roman Empire, Vlachs were recognized as those who spoke Latin, the official language of the Byzantine Empire used only in official documents, until the 7th century when it was changed to the more popular Greek.

The Pannonian Avars (Abaroi or Varchonitai Βαρχονίτες, Varchonítes, or Pseudo-Avars in Byzantine sources) were an alliance of several groups of Eurasian nomads. They are probably best known for their invasions and destruction in the Avar–Byzantine wars from 568 to 626. The name Pannonian Avars (after the area in which they eventually settled) is used to distinguish them from the Avars of the Caucasus, a separate people with whom the Pannonian Avars might or might not have had links. They established the Avar Khaganate, which spanned the Pannonian Basin and considerable areas of Central and Eastern Europe from the late 6th to the early 9th century. Although the name Avar first appeared in the mid-5th century, the Pannonian Avars entered the historical scene in the mid-6th century, on the Pontic-Caspian steppe as a people who wished to escape the rule of the Göktürks. The earliest clear reference to the Avar ethnonym comes from Priscus the Rhetor (died after 472 AD). Priscus recounts that, c. 463, the Šaragurs, Onogurs and Ogurs were attacked by the Sabirs, who had been attacked by the Avars. In turn, the Avars had been driven off by people fleeing "man-eating griffins" coming from "the ocean". The next author to discuss the Avars, Menander Protector, appeared during the 6th century, and wrote of Göktürk embassies to Constantinople in 565 and 568 AD. The Turks appeared angry at the Byzantines for having made an alliance with the Avars, whom the Turks saw as their subjects and slaves. Turxanthos, a Turk prince, calls the Avars "Varchonites" and "escaped slaves of the Turks", who numbered "about 20 thousand".

In 557 the Avars sent an embassy to Constantinople, marking their first contact with the Byzantine Empire, presumably from the northern Caucasus. In exchange for gold, they agreed to subjugate the "unruly gentes" on behalf of the Byzantines. They conquered and incorporated various nomadic tribes, Kutrigurs and Sabirs, and defeated the Antes. By 562 the Avars controlled the lower Danube basin and the steppes north of the Black Sea. By the time they arrived in the Balkans, the Avars formed a heterogeneous group of about 20,000 horsemen. After the Byzantine Emperor Justinian I bought them off, they pushed northwestwards into Germania. However, Frankish opposition halted the Avars' expansion in that direction. Seeking rich pastoral lands, the Avars initially demanded land south of the Danube River in present-day Bulgaria, but the Byzantines refused, using their contacts with the Göktürks as a threat against Avar aggression. The Avars turned their attention to the Carpathian Plain and to the natural defenses it afforded. However, the Carpathian basin was then occupied by the Gepids. In 567 the Avars formed an alliance with the Lombards, enemies of the Gepids, and together they destroyed much of the Gepid Kingdom. The Avars then persuaded the Lombards to move into northern Italy, an invasion that marked the last Germanic mass-movement in the Migration Period. Continuing their successful policy of turning the various barbarians against each other, the Byzantines persuaded the Avars to attack the Sclavenes in Scythia Minor (modern Dobruja), a land rich with goods. After devastating much of the Sclavenes' land, the Avars returned to Pannonia after many of the Khagan's subjects deserted to the Byzantine Emperor.

By about 580, the Avar Khagan Bayan I had established supremacy over most of the Slavic, Bulgar and Germanic tribes living in Pannonia and the Carpathian Basin. When the Byzantine Empire was unable to pay subsidies or hire Avar mercenaries, the Avars raided their Balkan territories. According to Menander, Bayan commanded an army of 10,000 Kutrigur Bulgars and sacked Dalmatia in 568, effectively cutting the Byzantine terrestrial link with North Italy and Western Europe. The Avar–Byzantine wars were a series of conflicts between the Byzantine Empire and the Avar Khaganate. The conflicts were initiated in 568, after the Avars arrived in Pannonia, and claimed all the former land of the Gepids and Lombards as their own. This led to them attempting to seize the city of Sirmium from Byzantium, which had previously retaken it from the Gepids, without success. Most of their future conflicts came as a result of raids by the Avars, or their subject Slavs, into the Balkan provinces of the Byzantine Empire. The Avars usually raided the Balkans when the Byzantine Empire was distracted elsewhere, typically in its frequent wars with the Sassanid Empire in the East. As a result, they often raided with impunity for long periods of time, before Byzantine troops could be freed from other fronts to be sent on punitive expeditions. This happened during the 580s and 590s, where Byzantium was initially distracted in the Byzantine–Sasanian War of 572–591, but then followed up by a series of successful campaigns that pushed the Avars back.

In 599 Byzantine generals Priscus and Comentiolus led their troops downstream to Viminacium, and crossed the river Danube. Once on the north bank, they defeated the Avars in the Battles of Viminacium. This battle was significant, as it was the first time the Avars suffered a major defeat in their home territory (mainly Hungary), and also led to the deaths of several of Bayan's sons, leader of Avars. After the battle, Priscus led his forces north into the Pannonian plain, engaging and defeating the Avars deep within their heartland. Comentiolus meanwhile remained near the Danube, to guard it. Priscus devastated the lands east of the river Tisza, inflicting heavy casualties on the Avars and Gepids, and defeating them in two further battles on the banks of the Tisza. In autumn 599, Comentiolus reopened the Gates of Trajan, which had not been used by the Byzantines for decades. In 601 Peter led troops to the banks of the Tisza, to defend the Danube cataracts, which were vital to the Byzantine Danube fleet's access to the cities of Sirmium and Singidunum. The next year, in 602, the Slavic Antes began to invade the Avars' land,  were already on the brink of collapse due to the uprisings of several Avar tribes, one of whom even defected to the Byzantines.

After being beaten back by the Byzantines under Murice, the Avars shifted their focus to Italy, establishing diplomatic contact in 603, and attempting an invasion of North Italy in 610. The Balkan frontier was largely pacified, for the first time since the reign of Anastasius I (r. 491–518). Maurice planned to repopulate the devastated lands which the Byzantines had recovered by settling Armenian peasants, as well as romanizing the Slav settlers already in the area. Maurice also planned to lead further campaigns against the Avar Khaganate, so as to either destroy them or force them into submission. However Emperor Maurice was overthrown in 602 by Phocas, as his army rebelled at the endless Balkan campaigning. Phocas promptly scrapped those plans. Phocas maintained the security of the Balkans during his reign from 602 to 610, although he did withdraw some forces from the Balkans in 605, in order to use them in the ongoing Byzantine-Sassanid War of 602–628. There is no archaeological evidence of Slav or Avar incursions during this time. While the lack of Byzantine action encouraged the Avars, they did not attack Byzantine territory until c. 615, when Emperor Heraclius (r. 610–641) withdrew his troops stationed in the Balkans in order to fight the Persian advance in the East.

The Avars, who were likely encouraged by their successful campaigns against the Lombards in 610 and the Franks in 611, resumed their incursions some time after 612. By 614, with the Persian capture of Jerusalem, it became clear to the Avars and their Slav subjects that retaliation from the Byzantines was extremely unlikely. Chronicles of the 610s record wholesale pillaging, with cities such as Justiniana Prima and Salona succumbing. The cities of Naissus and Serdica were captured in 615, and the cities of Novae and Justiniana Prima were destroyed in 613 and 615, respectively. The Slavs also raided in the Aegean, as far as Crete, in 623. During this time period, there were three separate sieges of Thessalonica: in 604, 615, and 617. In 623 the Byzantine emperor Heraclius journeyed into Thrace in an attempt to agree peace with the Avar Khagan face to face. Instead the Byzantines were ambushed, with Heraclius narrowly escaping and most of his bodyguard and retainers being killed or captured. The Avar raids continued, culminating in the Siege of Constantinople in 626, where the Avars were finally defeated.

The Persian king Khosrau II, after suffering reverses through Heraclius' campaigns in the Persian rear, resolved to launch a decisive strike. While general Shahin Vahmanzadegan was sent to stop Heraclius with 50,000 men, Shahrbaraz was given command of a smaller army and ordered to slip by Heraclius' flank, and march for Chalcedon, a Persian base across the Bosporus from Constantinople. Khosrau II also made contact with the Khagan of the Avars to allow for a coordinated attack on Constantinople, the Persians on the Asiatic side, and the Avars from the European side. The Avar army approached Constantinople from Thrace and destroyed the Aqueduct of Valens. Because the Byzantine navy controlled the Bosporus strait, the Persians could not send troops to the European side to aid the Avars, which deprived the Avars of the Persian expertise in siege warfare. Byzantine naval superiority also made communication between the two forces difficult. 

Constantinople's defenders were under the command of Patriarch Sergius and the patrician Bonus. On 29 June 626, the Avars and Persians began a coordinated assault upon the walls. The Byzantine defenders had 12,000 well-trained cavalry troops, who were likely dismounted, facing roughly 80,000 Avars and Sclaveni (Slavs). Because the Persian base in Chalcedon had been established for many years, it was not immediately obvious that a siege would take place. It only became obvious to the Byzantines after the Avars began to move heavy siege equipment towards the Theodosian Walls. Although the walls were continuously bombarded for a month, morale was high in the city; Patriarch Sergius bolstered morale by leading processions along the tops of the walls, carrying the Blachernitissa icon of the Virgin Mary. The peasantry around Constantinople were rallied by this religious zeal, especially because both forces attacking Constantinople were heathens. On August 7, a fleet of Persian rafts ferrying troops across the Bosporus to the European side were surrounded and destroyed by the Byzantine fleet. The Sclaveni then attempted to attack the Sea Walls from across the Golden Horn, while the Avars attacked the land walls. However, the Sclaveni boats were rammed and destroyed by the galleys of Bonus, and the Avar land assaults on August 6th and 7th were repelled. The news that the Emperor's brother Theodore had decisively defeated Shahin arrived, leading the Avars to retreat to the Balkan hinterland within two days. They would never seriously threaten Constantinople again. Even though the Persian army of Shahrbaraz still remained at Chalcedon, the threat to Constantinople was over, as the Persians could not use artillery from their side of the Bosporus. In thanks for the lifting of the siege and the supposed divine protection granted by the Virgin Mary, the celebrated Akathist Hymn was written by an unknown author, possibly Patriarch Sergius or George of Pisidia.

In the 630s, Samo, the ruler of the first historically known Slavic polity known as Samo's Tribal Union or Samo's realm, increased his authority over lands to the north and west of the Khaganate at the expense of the Avars, ruling until his death in 658. The Chronicle of Fredegar recorded that during Samo's rebellion in 631AD, 9,000 Bulgars led by Alciocus left Pannonia to modern-day Bavaria where Dagobert I massacred most of them. The remaining 700 joined the Wends. At about the time of Samo's realm, the Kubrat of the Dulo clan led a successful uprising to end Avar authority over the Pannonian Plain; he established what the Byzantines used to call Patria Onoguria, "the homeland of Onogurs". The civil war, possibly a succession struggle in Onoguria between the joint Kutrigur and Utigur forces, raged from 631 to 632. The power of the Avars' Kutrigur forces was shattered and the Avars came under the control of Patria Onoguria. Also at the same time, according to Constantine VII's work De Administrando Imperio (10th century), a group of Croats separated from the White Croats who lived in White Croatia and arrived by their own will, or were called by the Byzantine Emperor Heraclius (610-641), to fight and defeat the Avars after which they eventually organized their own principality in Dalmatia. After failing to capture Constantinople, the Avars rapidly began to decline before disintegrating entirely, due to both internal power struggles, and conflicts with the Bulgars and Sclaveni. After their hegemony over various tribal peoples collapsed, their land was further reduced by the Bulgars around 680, leaving behind a rump state which remained until their conquest by Charlemagne, starting in 790 and ending in 803.
Πηγή : https://en.m.wikipedia.org/wiki/Avar%E2%80%93Byzantine_wars
https://en.m.wikipedia.org/wiki/History_of_the_Balkans
https://en.m.wikipedia.org/wiki/Pannonian_Avars