The Balto-Slavic languages are a branch of the Indo-European family of languages. It traditionally comprises the Baltic and Slavic languages. Baltic and Slavic languages share several linguistic traits not found in any other Indo-European branch, which points to a period of common development. Although the notion of a Balto-Slavic unity has been contested (partly due to political controversies), there is now a general consensus among specialists in Indo-European linguistics to classify Baltic and Slavic languages into a single branch, with only some details of the nature of their relationship remaining in dispute.
A Proto-Balto-Slavic language is reconstructable by the comparative method, descending from Proto-Indo-European by means of well-defined sound laws, and out of which modern Slavic and Baltic languages descended. One particularly innovative dialect separated from the Balto-Slavic dialect continuum and became ancestral to the Proto-Slavic language, from which all Slavic languages descended.
The nature of the relationship of the Balto-Slavic languages has been the subject of much discussion from the very beginning of historical Indo-European linguistics as a scientific discipline. A few are more intent on explaining the similarities between the two groups not in terms of a linguistically "genetic" relationship, but by language contact and dialectal closeness in the Proto-Indo-European period.
This bipartite division into Baltic and Slavic was firs
This bipartite division into Baltic and Slavic was first challenged in the 1960s, when Vladimir Toporov and Vyacheslav Ivanov observed that the apparent difference between the "structural models" of the Baltic languages and the Slavic languages is the result of the innovative nature of Proto-Slavic, and that the latter had evolved from an earlier stage which conformed to the more archaic "structural model" of the Proto-Baltic dialect continuum. Frederik Kortlandt (1977, 2018) has proposed that West Baltic and East Baltic are in fact not more closely related to each other than either of them is related to Slavic, and Balto-Slavic therefore can be split into three equidistant branches: East Baltic, West Baltic and Slavic.
Alternative Balto-Slavic tree model
The tripartite split is supported by glottochronologic studies by V. V. Kromer,glottochronologic studies by V. V. Kromer, whereas two computer-generated family trees (from the early 2000s) that include Old Prussian have a Baltic node parallel to the Slavic node.
The sudden expansion of Proto-Slavic in the sixth and the seventh century (around 600 CE, uniform Proto-Slavic with no detectable dialectal differentiation was spoken from Thessaloniki in Greece to Novgorod in Russia[dubious ]) is, according to some, connected to the hypothesis that Proto-Slavic was in fact a koiné of the Avar state, i.e. the language of the administration and military rule of the Avar Khaganate in Eastern Europe. In 626, the Slavs, Persians and Avars jointly attacked the Byzantine Empire and participated in the Siege of Constantinople. In that campaign, the Slavs fought under Avar officers. There is an ongoing controversy over whether the Slavs might then have been a military caste under the khaganate rather than an ethnicity. Their language—at first possibly only one local speech—once koinéized, became a lingua franca of the Avar state. This might explain how Proto-Slavic spread to the Balkans and the areas of the Danube basin, and would also explain why the Avars were assimilated so fast, leaving practically no linguistic traces, and that Proto-Slavic was so unusually uniform. However, such a theory fails to explain how Slavic spread to Eastern Europe, an area that had no historical links with the Avar Khanate.
That sudden expansion of Proto-Slavic erased most of the idioms of the Balto-Slavic dialect continuum, which left us today with only two groups, Baltic and Slavic (or East Baltic, West Baltic, and Slavic in the minority view). This secession of the Balto-Slavic dialect ancestral to Proto-Slavic is estimated on archaeological and glottochronological criteria to have occurred sometime in the period 1500–1000 BCE. Hydronymic evidence suggests that Baltic languages were once spoken in much wider territory than the one they cover today, all the way to Moscow, and were later replaced by Slavic.
Common Balto-Slavic innovations include several other changes, which are also shared by several other Indo-European branches. These are therefore not direct evidence for the existence of a common Balto-Slavic family, but they do corroborate it.
Some examples of words shared among most or all Balto-Slavic languages:
Despite lexical developments exclusive to Balto-Slavic and otherwise showing evidence for a stage of common development, there are considerable differences between the vocabularies of Baltic and Slavic. Rozwadowski noted that every semantic field contains core vocabulary that is etymologically different between the two branches. Andersen prefers a dialect continuum model where the northernmost dialects developed into Baltic, in turn, the southernmost dialects developed into Slavic (with Slavic later absorbin
Despite lexical developments exclusive to Balto-Slavic and otherwise showing evidence for a stage of common development, there are considerable differences between the vocabularies of Baltic and Slavic. Rozwadowski noted that every semantic field contains core vocabulary that is etymologically different between the two branches. Andersen prefers a dialect continuum model where the northernmost dialects developed into Baltic, in turn, the southernmost dialects developed into Slavic (with Slavic later absorbing any intermediate idioms during its expansion). Andersen thinks that different neighboring and substratum languages might have contributed to the differences in basic vocabulary.