Slavic migrations to the Balkans

Exhausted by several factors and reduced to the coastal parts of the Balkans, Byzantium was not able to wage war on two fronts and regain its lost territories, so it reconciled with the establishment of Sklavinias and created an alliance with them against the Avar and Bulgar Khaganates.

Various factors, including the Late Antique Little Ice Age and population pressure, pushed the migration of the Early Slavs, who since the mid-6th century were also led by the Pannonian Avars.

[14] Procopius recorded that in 518 a large army of the Antae, "who dwell close to the Sclaveni", crossed the Danube River into Roman territory,[15] but suffered a bad defeat by magister militum per Thraciam Germanus.

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.

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.

[35] According to Procopius, around summer 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.

[16][38] 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.

[36][28] 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.

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", Sclaveni captured the standard of Constantianus, went 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.

[16][40] In the same year or early 552,[40][41] another throng of Sclaveni 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 doing so enabling a route avoiding defensive forts on the limes and enter Upper Moesia, Illyricum, Thrace up to Constantinople[42]): And the Emperor Justinian sent an army against them commanded by the sons of Germanus with others.

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.

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 ...

This allowed Slav tribes to stay together regardless of environmental factors, but according to Johannes Koder, "impeded coordinated military resistance against the enemy", which put them in a situation of being under foreign political leadership.

[59][72] When the Slavs and later the Avars entered the southeast of Europe they lacked advanced siege-warfare tactics, but around 587 they acquired this knowledge from contact with Byzantine culture, and because of this no urban settlement or fort could oppose them any more.

[86] 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.

[87] 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".

[99] In the northern regions of the Carpathian Basin (from Tisza River to Western Slovakia) the presence of Slavs is archaeologically confirmed in the first half of the 6th century.

[89] Based on findings of different types of fibulae and pottery identified with the Slavs on banks of Danube around Iron Gates, and their analogies, archaeologists hypothesize movement of a part of Slavs from an area of today's Serbian Danube in southeast direction through Southern Bulgaria-Constantinople-Asia Minor, and south direction along Great Morava and Vardar river to Thessaly and Peloponnese.

[137] The distribution of the cremation burials and archaic Prague-pottery associated with the early Slavs shows higher density at the periphery, especially western, of the Avar Khaganate in the Middle Danube region.

[140] A mid-6th century graves with prestigious artefacts found at Regensburg-Grossprüfening in Bavaria indicate resettlement of an elite Pannonian-Middle Danubian Slavic military group running away from the Avar expansion in the western part of the Carpathian Basin.

[143] The territory of Upper and Lower Austria was settled by Slavs of Prague-Korchak culture (with some additional migrations from the north, and Carantania[144]), who were steadily assimilated by the Bavarians.

[152] Zbigniew Gołąb, partly based on Oleg Trubachyov research, concluded that the "main route taken by the ancestors of the Southern Slavs in their migration south towards the Danube was the ancient trail through the central Carpathian passes ... northeastern Pannonia i.e., later sub-Carpathian Ruthenia.

[166][167] A bundle of isoglosses between them around the Serbian-Bulgarian boundary could be explained by different hypotheses, most probably existence of Romance and Albanian-speaking population and eastward movement of Western South Slavs.

[171] The migrations of ancient Proto-Slavic dialectisms possibly can be seen in the vocabulary, like in the distribution of lexemes "dъždь-kiša", "*želězo-gvožđe", "*sad´a-čađ",[172][173] and words for different types of plough.

[175] Ludmila Vergunova in her research of lexical isoglosses of Proto-Slavic words (e.g. *polnъ, *gora, *golь/*golina, *dĕlъ, *bьrdo, *slopъ, *solpъ, *skokъ, *bъlkъ/*bъlčь, *jьzvorь, *pьrtь, *brьvь/*brьva, *rapa/*ropa, *bara) and South Slavic lexical synonyms (*vatra/*ogьnь; *kqtja/*hiža/*izba; *sedlo/*vьsь; *lĕsь/gvozd; *ostrovъ/*otokъ) found that "Ukrainian Carpathian and sub-Carpathian dialects and east Slovak dialects ... have numerous correspondences with the southeastern part of the central Balkan peninsula", while Slovenian, Kajkavian, (Northern) Chakavian-island and some Macedonian dialects "do not share ancient lexical and semantic isoglosses with the east Carpathian region", possibly being "remnants of the language of the first wave of Slavic settlers of the era of Avar-Slavic contacts".

[176] Joseph Schallert and Marc L. Greenberg regarding the distribution of lexeme "*gъlčěti" (in the same meaning of verb 'speak, talk' like "*govoriti", but also onomatopoeic 'make noise' and pejorative 'scold'), concluded it was brought from northeastern Danubian plain to Bulgaria, but also to Slovenia and Croatia (with Slovene Pannonian dialect group probably being of southeastern Danube-Sava basin origination), but has total absence in other Shtokavian-speaking countries and Macedonia.

[184] Based on toponymic research, Iordan Zaimov considered that the Slavs crossed Danube around Vidin, smaller wave went eastward alongside the river, while the main wave went southward alongside Timok and Great Morava rivers, divided into two sub-waves, one went to Macedonia, Tessaly, Albania (where formed so-called Komani-Kruja culture[185]), Greece, Peloponnese and Crete, another went to the northern coast of the Aegean Sea and Sea of Marmara.

[89] P. Ivić considered that the linguistic evidence is in contradiction with the arrival of Croats and Serbs from northwest as described in DAI,[186] F. Dvornik argued they could not make a linguistic influence because arrived as a small elite,[187] while A. Loma concluded that the DAI account "corresponds to the truth" as onomastic evidence supports migration of the Serbs and Croats from an area between rivers Elbe and Vistula.

[191] Jouko Lindstedt and Elina Salmela also concluded that the spread of Proto-Slavic was due to migration and founder effect, and "not attributable to a lingua-franca function in a great area, as is often surmised", because such reasoning is contradicted with lack of historical knowledge about the languages in use in the Avar Khaganate, lack of Avar's influence outside of the Carpathian Basin, the fact that the Slavs became widespread ethnic population before the arrival of the Avars, and "the Slavic of the expansion period does not exhibit changes that are typical of lingua francas ... Late Proto-Slavic (or Common Slavic) remained a morphologically complex language, and its complicated accentological system in particular ... shows no trace of a possible lingua-franca function".

[198] The 2006 Y-DNA study results "suggest that the Slavic expansion started from the territory of present-day Ukraine, thus supporting the hypothesis that places the earliest known homeland of Slavs in the basin of the middle Dnieper".