, showing the location of
Sclaveni,
Antae,
Gepids,
Lombards and
Heruli (per Pavlovič 2017; Filipec 2020). The Slavs who settled in Southeast Europe comprised two groups: the
Antae and the
Sclaveni. The first certain Slavic raids date to the early 6th century during the time of the Eastern Roman Emperor
Justin I (), coinciding with the end of the
Vitalian revolt of 511–518.
Procopius recorded that in 518 a large army of the Antae, "who dwell close to the Sclaveni", crossed the Danube River into Roman territory, but suffered a bad defeat by
magister militum per Thraciam Germanus. In 536, some 1,600 horsemen of Slavs,
Huns and Antae arrived in Italy as Byzantine reinforcement to rescue
Belisarius, serving also as horsearchers. Raids continued with ever-faster and stronger incursions during the time of
Justinian I (), with Procopius recording that the whole of
Illyricum and
Thrace (killing its magister militum
Chilbudius) was pillaged almost every year by Huns, Sclaveni, and Antae, who with each incursion did enormous damage to the native Roman population, making the region a "Scythian desert".
Jordanes considered the devastation wrought by Slavs to be a
divine punishment for the Roman sins. They also possibly participated in the devastating 539/540 winter raid of the
Huns which covered lands from the Adriatic coast to the Constantinople. Around the 540s the Sclaveni accepted the exiled Lombard prince Ildigis/Hildigis son of Risiulfus who was escaping from
Audoin-
Thurisind's conflict and helped him to organise his own army of 6,000 Gepids and Sclaveni which temporarily supported Thurisind's case, and
Totila of
Goths in Italy, but the exact location of the Slavs in question remains a matter of scholarly debate (but most probably in the Carpathian Basin near the Danubian frontier). For a great throng of the barbarians, Sclaveni, had, as it happened, recently crossed the river Ister, plundered the adjoining country and enslaved a very great number of Romans ... Huns and Antae and Sclaveni had already made the crossing many times and done irreparable harm to the Romans ... At about this time [548] an army of Sclaveni crossed the river Ister [Danube] and spread desolation throughout the whole of Illyricum as far as
Epidamnus, killing or enslaving all who came in their way, young and old alike and plundering their property. And they had already succeeded in capturing numerous strongholds of that region, which were then quite undefended, but which previously had been reputed to be strong places, and they continued to roam about searching out everything at their own pleasure. And the commanders of the Illyrians kept following them with an army of 15,000 men, without, however, having the courage to get close to the enemy. At about this time [549] an army of Sclaveni amounting to not more than 3,000 crossed the
Ister River without encountering any opposition, advanced immediately to the
Hebrus River, which they crossed with no difficulty, and then split into two parts. Now the one section of them contained 1,800 men, while the other comprised the remainder. And although the two sections were thus separated from each other, the commanders of the Roman army, upon engaging with them, both in Illyricum and in Thrace, were defeated unexpectedly, and some of them were killed on the field of battle, while others saved themselves by a disorderly flight. Now after all the generals had fared thus at the hands of the two barbarian armies, though they were far inferior to the Roman forces in number, one section of the enemy engaged with
Asbadus. This man was a guard of the Emperor Justinian, since he served among the candidati as they are called, and he was also commander of the cavalry cohorts which from ancient times have been stationed at
Tzurullum, the fortress in Thrace, a numerous body of the best troops. These too the Sclaveni routed with no trouble, and they slew the most of them in a most disgraceful flight ... Having accomplished these things, they turned to plunder all the towns, both of Thrace and of Illyricum, in comparative security; and both armies captured many fortresses by siege ... Then those who had defeated Asbadus plundered everything in order as far as the sea and captured by storm a city on the coast named
Topirus ... Then they slew all the men immediately, to the number of 15,000, took all the valuables as plunder, and reduced the children and women to slavery. Before this, however, they had spared no age, but both these aud the other group, since the time when they fell upon the land of the Romans, had been killing all who fell in their way, young and old alike, so that the whole land inhabited by the Illyrians and Thracians came to be everywhere filled with unburied corpses ... Thus did the Sclaveni consistently destroy those who fell in their way. But from this time onward both these and those of the other group, being as it were drunk with the great quantity of blood they had shed, saw fit to make prisoners of some who fell into their hands, and consequently they were taking with them countless thousands of prisoners when they all departed on the homeward way. At one point in the late 530s or early 540s, the Sclaveni and Antae "became hostile to one another and engaged in a battle, in which it so fell out that the Antae were defeated by their opponents". In 545 Justinian I managed to make an alliance with the Antae to stop
Hunnic intrusions into the
Lower Danube area, but this caused more Sclaveni intrusions from the Middle Danube region. According to Procopius, around the summer of 550 a massive number of Sclaveni "such as never before was known arrived on Roman soil, having crossed the Ister River and come to the vicinity of
Naissus", planning to capture by siege
Thessalonica and near cities. Hearing that Germanus was organizing large forces in
Serdica southeast of Naissus (initially with plans for a
campaign against Totila's Goths in Italy, but now devoted to repel Sclaveni's invasion; meanwhile
Narses had to deal with
Kutrigurs around
Philippopolis), the Sclaveni abandoned their initial plans and crossed the
Dinaric Alps mountain ranges of Illyricum and came into the province of Dalmatia. Germanus soon died, and the army now led by his son-in-law
John (nephew of Vitalian) and son
Justinian was ordered to start marching to Dalmatia, pass the winter in
Salona and then move from there to
Ravenna. By the time they entered the province of Dalmatia, the first group of Sclaveni was joined by a second group who also crossed the Danube, and "overrun the Roman domain with complete freedom ... divide themselves into three groups and wrought irreparable damage ... not merely plundering that country by sudden raids, but actually spending the winter as if in their own land and having no fear of the enemy", disabling Roman armies movement to Ravenna but not engaging in battle. Procopius reported that some thought that the Sclaveni were invited with large sums of money by Totila to divert emperor's forces from attacking the Goths in Italy by land. Eventually, emperor Justinian decided to assemble a large army led by the commanders John, Narses,
Constantianus,
Aratius,
Justin (eldest son of Germanus), and supreme commander
Scholasticus (imperial eunuch). They clashed in spring 551 with one of the three groups of Slavs near
Adrianopolis in Thrace, where "Romans were decisively vanquished. In that battle many of the best soldiers perished, and the generals came within a little of falling into the hands of the enemy, succeeding only with difficulty in making their escape with the remnant of the army and thus saving themselves, each as best he could", the Sclaveni captured the standard of Constantianus, went on to plunder
Astica and reached the
Anastasian Wall, where Roman forces managed a victory over a part of the barbarian forces, retrieving the standard and rescued many Roman captives, but nevertheless the Sclaveni departed with large looting. In the same year or early 552, another
throng of Sclaveni and 12,000 Kutrigurs attacked Illyricum "and inflicted sufferings there not easily described", helped twice by the Gepids to cross the Danube (as Gepids controlled the river passages of the Middle Danube, Sava and Drava, including territory around
Sirmium, and in doing so enabled a route avoiding defensive forts on the limes and enter
Upper Moesia, Illyricum, Thrace up to Constantinople): And the Emperor Justinian sent an army against them commanded by the sons of Germanus with others. But since this army was far outnumbered by the enemy, it was quite unable to engage with them, but remained always in the rear and cut down the stragglers left by the barbarians. And they slew many of them but took some few prisoners, whom they sent to the emperor. But nevertheless these barbarians continued their work of devastation. And spending as they did a long time in this plundering expedition, they filled all the roads with corpses, and enslaved countless multitudes and pillaged everything without meeting any opposition; then finally they departed on the homeward journey with all their plunder. Nor could the Romans ambuscade them while crossing the Ister River or harm them in any other way, since the Gepaedes, having engaged their services, took them under their protection and ferried them across, receiving large payment for their labour. For the payment was at the rate of one gold stater per head. At this the emperor was grievously vexed, seeing that for the future he had no possible means of checking the barbarians when crossing the Ister River in order to plunder the Roman domain, or when taking their departure from such expeditions with the booty they gained, and he wished for these reasons to enter into some sort of treaty with the nation of the Gepaedes ... But not long after this, when the Lombards according to the terms of their alliance requested an army to fight with them against the Gepaedes, the Emperor Justinian sent it, laying the charge against the Gepaedes that after the treaty they had transported certain of the Sclaveni across the Ister River to the detriment of the Romans. elite in the 6th and 9th area. The Avar Khaganate, which formed on the territory previously occupied by
Gepids,
Lombards and
Sclaveni, was a multi-ethnic society. and
White Croats, per V.V. Sedov (1979). in the 7th century. In response to the Sclaveni and Kutrigur intrusion, Justinian paid the Utrigurs to attack the Kutrigurs' homeland, which temporarily resolved the situation.As a response against the Slavic intrusions, the Byzantines supported the Lombards against the Gepids, which led to the defeat of the Gepids at the Battle of Asfeld, which compelled the Gepids to return to their previous alliance with the empire and to stop ferrying raiders. Additionally, Justinian I succeeded in realizing an extensive building program of more than 600 forts across three defensive lines in the Balkans, because of which there were no recorded independent raids of the Sclaveni between 552 and 577. In 558/559 some Sclaveni joined the Kutrigurs led by
Zabergan in their devastating invasion of the Balkans, (
though Belisarius was able to defeat and repel their invasion), and in 568 the Kutrigurs raided Dalmatia as well. Historical circumstances substantially changed with the arrival of the
Pannonian Avars (after the complete
fall of the Gepids (567) and the departure of
Lombards in 568), who fought against the Antae and subjugated masses of both Antae (562, but maintained independence as Byzantine allies until 602) and the Sclaveni (Pannonian-Middle Danubian Slavs lost their independence to the Avars between 571 and 578, while Lower Danube/Wallachian Slavs were active on their own although as Avar allies since 585). It is considered unlikely that the Avars ruled over all the Slavs in the Danube region at one time, and "whether autonomously or under commission from the Avars", they continued to make incursions into the Roman territory. After the death of Justinian I, the new Roman Emperor
Justin II () halted the payment of subsidies to the Avars, thus sparking an
almost century-long war (568–626). With the Byzantines preoccupied with the
572–591 and
602–628 wars with the
Sasanian Empire, Avars and Slavs continued devastating intrusions along the Byzantine borders from Northern Italy to Southern Greece, and by the mid-7th century, the Slavs had settled in all the
Balkans and
Peloponnese.
Menander Protector recorded that in fourth year of joint rule of emperors
Justin II and
Tiberius II Constantine (578), some 100,000 Lower Danube/Wallachian Sclaveni ravaged the province of Thrace and many other areas.
John of Biclaro mentions that the Sclaveni plundering was even near the walls of Constantinople. Tiberius managed to make a short-term alliance with Avar khagan
Bayan I, whose envoy to Slavic chief
Daurentius was refused and murdered, and some 60,000 Avar horsemen aided by Byzantine
quaestura exercitus and
magister militum of Illyricum, Iohannes, attacked Slavic settlements, whose population sought shelter in the woods. The Avar attack liberated some Byzantines who were captives and fortifications, though it did not change the chaotic situation in the region as in the next year another Avar-Roman envoy in Illyricum was ambushed by the Sclaveni, while the khagan was planning for the downfall of the Byzantine defense system. Based on the archaeological research of forts, the Avar-Slav devastation of Dalmatia happened in the late 560s and early 570s, with limited inhabitation until the end of the 6th century. The Byzantine Emperor
Maurice () in his
Balkan campaigns (582–602) did not manage to stop the successful siege of
Sirmium (580 to 582), though his generals triumphed at
Battles of Viminacium (599; also capturing 8,000 Sclaveni), and dealing with Lower Danube/Wallachian Sclaveni
rex Musokios and chieftains
Ardagast and
Peiragastus (593–594). In 599, the Byzantine general Priscus managed to win four victories against the Avars in their homeland, which killed tens of thousands of Avars. Eventually, by 602 Maurice had kept the Avars and Slavs out and successfully re-established the Danube as the border of the empire. However, following the overthrow of Maurice and the resumption of Byzantine-Persian warfare, the Byzantine position in the Balkans declined. Subsequently, the
siege of Thessalonica (617; causing the complete collapse of
minting coins there), and the destruction of various cities including
Justiniana Prima and
Salona, culminated with the unsuccessful
Siege of Constantinople (626). After the siege, somewhere between 628 and 629,
George of Pisidia reported that the Slavs and Avars were fighting "which prevented them from waging a common war", indicating that the Pannonian Slavs managed to liberate themselves from the Avar rule, which itself coincides with the account in
De Administrando Imperio about the
Croat-Avar
war in the Roman province of Dalmatia. It was followed by settlement of the Croats and
Serbs in the province of Dalmatia (sometimes considered as movement of a military elite), which was accepted by emperor
Heraclius in the scope of bringing peace to the province and making an anti-Avar buffer zone. In the same time also happened, and possibly were related, successful revolt of West Slavs under
Samo in Central Europe and
Bulgars khan
Kubrat in Eastern Europe. With the destruction of Roman fortifications came a loss of Byzantine military and administrative power in Roman provinces. The native population was often decimated, and smaller or larger groups of Slavs settled in the devastated lands. Settlement among the natives, often replacing them, happened in the autumn, when winter supplies were secured for the people and animals. After mixing with the natives who survived in smaller communities, depending on the region, the Slavic tribes mostly had names of
toponymic origin. The Slavs established dense settlements in Southeast Europe, more precisely in the
Praetorian prefecture of Illyricum: • In the late Roman province of
Noricum was the
Slavic settlement of the Eastern Alps (including
Carantanians). • In
Pannonia were the
Pannonian Slavs (with
Pannonian Dulebes). • The province of
Dalmatia was settled by the
White Croats (and
Guduscani),
Serbs,
Narentines,
Zachlumians,
Travunijans, and
Kanalites. •
Praevalitana was settled by
Diocleans. • The provinces of
Moesia and
Dardania were inhabited by
Merehani,
Braničevci,
Timočani and
Praedenecenti. • The provinces of
Dacia Ripensis and Moesia Secunda were inhabited by
Seven Slavic tribes and
Severians. • In part of the
Diocese of Thrace were
Smolyani and
Strymonites. • In all of the
Diocese of Macedonia were numerous tribes of
Drougoubitai,
Berziti,
Sagudates,
Rhynchinoi,
Baiounitai,
Belegezites,
Melingoi and
Ezeritai. Also,
Thomas the Presbyter recorded in 623 that the Slavs "invaded
Crete and the other islands. There some blessed men of
Qēnneshrē were taken captive and some twenty of them were killed", and scholars consider that Slavic settlement on the island began in the mid-10th century. • Some Slavs in Thrace were also relocated to
Anatolia, and later became known as
Asia Minor Slavs. Eventually, the Slavs who had settled in the former Roman provinces of Pannonia and Dalmatia reached a substantial amount of autonomy or independence, establishing
Sklavinias influenced by both
Francia and the Byzantine Empire. In turn, the
Sklavinias across much of the former dioceses of
Dacia and
Thracia and the northern half of
Macedonia fell under the rule of the
First Bulgarian Empire. After the adoption of
Orthodox Christianity and
Slavonic as a state religion and language, respectively, and the complete
Slavicisation of the Turkic
Bulgars by the late 800s, the Slavs lost their separate tribal identities and loyalties, replacing them with an overarching
Bulgarian one. By contrast, due to lack of political organisation and a far greater number of surviving Greek communities, the Slavs in the south of the
Macedonian diocese quickly lost ground to the Byzantines, who recovered first
Attica and
Thessaly, then
Peloponnese, followed by
Chalkidiki and
Epirus, and after several
transfers of Greek speakers from
Italy and
Asia Minor, most local Slavs had been assimilated by the late 800s. The
Byzantine-Norman wars had a devastating effect on the Slavic speakers in the eastern and southern part of present-day
Albania, with surviving populations being assimilated into the Albanian-speaking majority. Slavic interaction with the native populations in the Eastern Balkans led to the formation of the
Balkan sprachbund.
Christianization After the settlement of the Slavs, Church administration – which was controlled by a thick network of Roman bishoprics – collapsed, and most of Southeast Europe turned to
paganism and entered the
Dark Ages, alongside most of post-Roman Europe. Many Slavs soon began to accept the cultural customs of the highly civilized Roman provinces, and in order to expand their cultural and state influence on the South Slavs, the
Roman Church and
Ecumenical Patriarchate of Constantinople began the process of
Christianization of the Slavs.
Martin of Braga already in 558 listed Slavs among baptized barbarians, most probably a reference to the Pannonian Slavs.
Pope Gregory I in May 591 advised bishops of Illyricum to accept their colleagues who taken refuge from invasions, in March 592 wrote to prefect of Illyricum about barbarian devastations, and by July 600 the Slavs were already attacking Eastern Adriatic coast. Some dioeceses vanished from historical sources, like
Virunum (
Zollfeld) and Poetovio (
Ptuj) by 579, Celea (
Celje) and
Emona (
Ljubljana) by 588, and
Teurnia (
Spittal an der Drau) and
Aguntum (
Lienz) by 591.
Pope Agatho in a letter to Byzantine emperor
Constantine IV regarding the
Third Council of Constantinople (680–681) mentioned that many Roman Church bishops are active "in the middle of the barbarians - the Lombards and Slavs, as well as the Franks, Goths and Britons". A mid-8th century episcopal notitia mentions Slavs among many others as part of the territorial jurisdiction of the Roman Church.
Lifestyle According to archaeological data and historical sources, the Slavs mostly travelled along the river valleys, but in the Southern Balkans, they travelled where they encountered greater resistance by the native
Byzantine Greek forces, along the mountain ranges. Soon after their arrival the Slavic archaeological culture changed under the influence of native and Byzantine cultures. They mostly were engaged in
agriculture, cultivating
proso millet, which they introduced,
wheat, but also
flax. They grew various fruits and vegetables, and learned
viticulture. They were actively engaged in
animal husbandry, using
horses for military and agricultural purposes, and raising
oxen and
goats. Those living in hilly terrain mostly lived as
shepherds. Those living near lakes, rivers, and seas also used various hooks and nets for fishing. They were known to be especially skilled in woodworking and shipbuilding, but also knew about metalworking and pottery. ==Archaeology and linguistics==