
The Balto-Slavic languages form a branch of the
Indo-European
The Indo-European languages are a language family native to the northern Indian subcontinent, most of Europe, and the Iranian plateau with additional native branches found in regions such as Sri Lanka, the Maldives, parts of Central Asia (e. ...
family of languages, traditionally comprising the
Baltic and
Slavic languages
The Slavic languages, also known as the Slavonic languages, are Indo-European languages spoken primarily by the Slavs, Slavic peoples and their descendants. They are thought to descend from a proto-language called Proto-Slavic language, Proto- ...
. Baltic and Slavic languages share several linguistic traits not found in any other Indo-European branch, which points to a period of common development and origin.
A
Proto-Balto-Slavic language is reconstructable by the
comparative method
In linguistics, the comparative method is a technique for studying the development of languages by performing a feature-by-feature comparison of two or more languages with common descent from a shared ancestor and then extrapolating backwards ...
, descending from
Proto-Indo-European
Proto-Indo-European (PIE) is the reconstructed common ancestor of the Indo-European language family. No direct record of Proto-Indo-European exists; its proposed features have been derived by linguistic reconstruction from documented Indo-Euro ...
by means of well-defined
sound laws
In historical linguistics, a sound change is a language change, change in the pronunciation of a language. A sound change can involve the replacement of one speech sound (or, more generally, one distinctive feature, phonetic feature value) by a ...
, and from 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
Proto-Slavic (abbreviated PSl., PS.; also called Common Slavic or Common Slavonic) is the unattested, reconstructed proto-language of all Slavic languages. It represents Slavic speech approximately from the 2nd millennium BC through the 6th ...
, from which all Slavic languages descended.
While the notion of a Balto-Slavic unity was previously contested largely due to political controversies, there is now a general consensus among academic specialists in Indo-European linguistics that Baltic and Slavic languages comprise a single branch of the Indo-European language family, with only some minor details of the nature of their relationship remaining in contention.
Historical dispute
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.

Baltic and Slavic share many close
phonological,
lexical,
morphosyntactic
In linguistics, morphology is the study of words, including the principles by which they are formed, and how they relate to one another within a language. Most approaches to morphology investigate the structure of words in terms of morphemes, wh ...
and accentological similarities (listed below). The early Indo-Europeanists
Rasmus Rask and
August Schleicher
August Schleicher (; 19 February 1821 – 6 December 1868) was a German linguist. Schleicher studied the Proto-Indo-European language and devised theories concerning historical linguistics. His great work was ''A Compendium of the Comparative Gr ...
(1861) proposed a simple solution: From Proto-Indo-European descended Balto-German-Slavonic language, out of which Proto-Balto-Slavic (later split into Proto-Baltic and Proto-Slavic) and Germanic emerged. Schleicher's proposal was taken up and refined by
Karl Brugmann, who listed eight innovations as evidence for a Balto-Slavic branch in the ''
Grundriss der vergleichenden Grammatik der indogermanischen Sprachen'' ("Outline of the Comparative Grammar of the Indo-Germanic Languages"). The
Latvia
Latvia, officially the Republic of Latvia, is a country in the Baltic region of Northern Europe. It is one of the three Baltic states, along with Estonia to the north and Lithuania to the south. It borders Russia to the east and Belarus to t ...
n linguist
Jānis Endzelīns thought, however, that any similarities among Baltic and Slavic languages resulted from intensive
language contact
Language contact occurs when speakers of two or more languages or varieties interact with and influence each other. The study of language contact is called contact linguistics. Language contact can occur at language borders, between adstratum ...
, i.e. that they were not genetically more closely related and that there was no common Proto-Balto-Slavic language.
Antoine Meillet (1905, 1908, 1922, 1925, 1934), a French linguist, in reaction to Brugmann's hypothesis, propounded a view according to which all similarities of Baltic and Slavic occurred accidentally, by independent parallel development, and that there was no Proto-Balto-Slavic language. In turn, the Polish linguist Rozwadowski suggests that the similarities among Baltic and Slavic languages are a result of both a genetic relationship and later language contact.
Thomas Olander corroborates the claim of genetic relationship in his research in the field of comparative Balto-Slavic
accentology.
Even though some linguists still reject a genetic relationship, most scholars accept that Baltic and Slavic languages experienced a period of common development. This view is also reflected in most modern standard textbooks on Indo-European linguistics. Gray and Atkinson's (2003) application of language-tree divergence analysis supports a genetic relationship between the Baltic and Slavic languages, dating the split of the family to about 1400 BCE.
Internal classification
The traditional division into two distinct sub-branches (i.e. Slavic and Baltic) is mostly upheld by scholars who accept Balto-Slavic as a genetic branch of Indo-European. There is a general consensus that the Baltic languages can be divided into East Baltic (Lithuanian, Latvian) and West Baltic (Old Prussian). The internal diversity of Baltic points at a much greater time-depth for the breakup of the Baltic languages in comparison to the Slavic languages.
"Traditional" Balto-Slavic tree model
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
Kortlandt's hypothesis is supported by a number of scholars. Some scholars
accept Kortlandt's division into three branches as the default assumption, but believe that there is sufficient evidence to unite East Baltic and West Baltic in an intermediate Baltic node.
The tripartite split is supported by
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.
Historical expansion
The sudden expansion of Proto-Slavic in the sixth and the seventh century (around 600 CE, uniform Proto-Slavic with minor dialectal differentiation was spoken from
Thessaloniki
Thessaloniki (; ), also known as Thessalonica (), Saloniki, Salonika, or Salonica (), is the second-largest city in Greece (with slightly over one million inhabitants in its Thessaloniki metropolitan area, metropolitan area) and the capital cit ...
in Greece to
Novgorod
Veliky Novgorod ( ; , ; ), also known simply as Novgorod (), is the largest city and administrative centre of Novgorod Oblast, Russia. It is one of the oldest cities in Russia, being first mentioned in the 9th century. The city lies along the V ...
in Russia) 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.
[Controversy discussed in ] 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 said, the Avar state was later replaced by the definitively Slavic state of
Great Moravia
Great Moravia (; , ''Meghálī Moravía''; ; ; , ), or simply Moravia, was the first major state that was predominantly West Slavic to emerge in the area of Central Europe, possibly including territories which are today part of the Czech Repub ...
, which could have played the same role.
It is also likely that the expansion of Slavic occurred with the assimilation of Iranic-speaking groups such as the
Sarmatians
The Sarmatians (; ; Latin: ) were a large confederation of Ancient Iranian peoples, ancient Iranian Eurasian nomads, equestrian nomadic peoples who dominated the Pontic–Caspian steppe, Pontic steppe from about the 5th century BCE to the 4t ...
, who quickly adopted Proto-Slavic due to speaking related Indo-European
satem languages, in much the same way
Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
expanded by assimilating the
Celtic speakers in continental Western Europe and the
Dacians
The Dacians (; ; ) were the ancient Indo-European inhabitants of the cultural region of Dacia, located in the area near the Carpathian Mountains and west of the Black Sea. They are often considered a subgroup of the Thracians. This area include ...
.
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
Moscow is the Capital city, capital and List of cities and towns in Russia by population, largest city of Russia, standing on the Moskva (river), Moskva River in Central Russia. It has a population estimated at over 13 million residents with ...
, and were later replaced by Slavic.
Shared features of the Balto-Slavic languages
The degree of relationship of the Baltic and Slavic languages is indicated by a series of common innovations not shared with other Indo-European languages, and by the relative chronology of these innovations which can be established. The Baltic and Slavic languages also share some inherited words. These are either not found at all in other Indo-European languages (except when borrowed) or are inherited from Proto-Indo-European but have undergone identical changes in meaning when compared to other Indo-European languages. This indicates that the Baltic and Slavic languages share a period of common development, the Proto-Balto-Slavic language.
Common sound changes
*
Winter's law: lengthening of vowels before Proto-Indo-European (PIE) non-breathy voiced consonants (''*b'', ''*d'', ''*g'').
* PIE breathy-voiced consonants (''*bʰ'', ''*dʰ'', ''*gʰ'', ''*ǵʰ'') merge into plain voiced consonants (''*b'', ''*d'', ''*g'', ''*ǵ''). This also occurred in several other Indo-European branches, but as Winter's law was sensitive to the difference between the two types of consonants, the merger must have happened after it and so is a specific Balto-Slavic innovation.
*
Hirt's law: retraction of the PIE accent to the preceding syllable, if that syllable ended in a laryngeal (''*h₁'', ''*h₂'', ''*h₃'', see
Laryngeal theory
The laryngeal theory is a theory in historical linguistics positing that the Proto-Indo-European (PIE) language included a number of laryngeal consonants that are not linguistic reconstruction, reconstructable by direct application of the com ...
).
* A high vowel is inserted before PIE syllabic
sonorant
In phonetics and phonology, a sonorant or resonant is a speech sound that is produced with continuous, non-turbulent airflow in the vocal tract; these are the manners of articulation that are most often voiced in the world's languages. Vowels a ...
s (''*l̥'', ''*r̥'', ''*m̥'', ''*n̥''). This vowel is usually ''*i'' (giving ''*il'', ''*ir'', ''*im'', ''*in'') but in some occasions also ''*u'' (''*ul'', ''*ur'', ''*um'', ''*un'').
Proto-Germanic
Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the linguistic reconstruction, reconstructed proto-language of the Germanic languages, Germanic branch of the Indo-European languages.
Proto-Germanic eventually developed from ...
is the only other Indo-European language that inserts a high vowel (''*u'' in all cases), all others insert mid or low vowels instead.
* Emergence of a
register distinction on long syllables, between acute (probably glottalized) and circumflex. The acute arose primarily when the syllable ended in a PIE voiced consonant (as in Winter's law) or when it ended in a laryngeal. The distinction is reflected in most Balto-Slavic languages, including Proto-Slavic, as an opposition between rising and falling tone on accented syllables. Some Baltic languages directly reflect the acute register in the form of a so-called "broken tone".
* Shortening of vowels before word-final ''*m''.
* Word-final ''*-mi'' > ''*-m'' after a long vowel.
This followed the preceding change, as the preceding long vowel is retained.
* Raising of stressed ''*o'' to ''*u'' in a final syllable.
* Merging of PIE short ''*o'' and ''*a'' into ''*a''. This change also occurred in several other Indo-European branches, but here too it must have happened after Winter's law: Winter's law lengthens ''*o'' to ''*ō'' and ''*a'' to ''*ā'', and must therefore have occurred before the two sounds merged. It also followed the raising of ''*o'' to ''*u'' above. In the Slavic languages, ''*a'' is later rounded to ''*o'', while the Baltic languages keep ''*a'':
** Lithuanian ''ašìs'' Old Church Slavonic ''ось'' (from PIE ''*a'': Latin ''axis'', Ancient Greek ''áxōn'')
** Lithuanian ''avìs'', Old Church Slavonic ''овьца'' (from PIE ''*o'': Latin ''ovis'', Greece ''óis'')
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.
*
Satemization: The PIE palatovelar consonants ''*ḱ'', ''*ǵ'', ''*ǵʰ'' become palatal sibilants ''*ś'', ''*ź'', ''*ź'', while the PIE labiovelar consonants ''*kʷ'', ''*gʷ'', ''*gʷʰ'' lose their labialization and merge with the plain velar ''*k'', ''*g'', ''*gʰ''. The palatal sibilants later become plain sibilants ''*s'', ''*z'' in all Balto-Slavic languages except Lithuanian.
*
Ruki sound law
The ruki sound law, also known as the ruki rule or iurk rule, is a historical sound change that took place in the satem branches of the Indo-European language family, namely in Balto-Slavic, Armenian, and Indo-Iranian. According to this sound ...
: ''*s'' becomes ''*š'' when preceded by ''*r'', ''*u'', ''*k'' or ''*i''. In Slavic, this ''*š'' later becomes ''*x'' (variously spelled , or in the Slavic languages) when followed by a back vowel.
Common grammatical innovations
* Replacement of the original PIE genitive singular ending of thematic (o-stem) nouns, which is reconstructed as ', with the ablative ending ''*-ād'' (Proto-Slavic ''*vьlka'', Lithuanian ''vil̃ko'', Latvian ''vilka''). Old Prussian, however, has another ending, perhaps stemming from the original PIE genitive: ''deiwas'' "god's", ''tawas'' "father's".
* Use of the ending ''*-ān'' (from earlier ''*-āmi'') of the instrumental singular in ā-stem nouns and adjectives.
This contrasts with Sanskrit ''-ayā'', archaic Vedic ''-ā''. Lithuanian ''rankà'' is ambiguous and could have originated from either ending, but the correspondence with East Lithuanian ''runku'' and Latvian ''rùoku'' point to Balto-Slavic ''*-ān''.
* Use of the ending ''*-mis'' in the instrumental plural, e.g. Lithuanian ''
sūnumìs'',
Old Church Slavonic
Old Church Slavonic or Old Slavonic ( ) is the first Slavic languages, Slavic literary language and the oldest extant written Slavonic language attested in literary sources. It belongs to the South Slavic languages, South Slavic subgroup of the ...
''
synъmi'' "with sons". This ending is also found in Germanic, while the other Indo-European languages have an ending with ''-bʰ-'', as in Sanskrit '.
* Creation of a distinction between definite (meaning similar to "the") and indefinite adjectives (meaning similar to "a"). The definite forms were formed by attaching the corresponding form of the relative/demonstrative pronoun ''*jas'' to the end of the adjective. For example, Lithuanian ''geràsis'' 'the good' as opposed to ''
gẽras'' 'good', Old Church Slavonic ''dobrъjь'' 'the good' as opposed to ''
dobrъ'' 'good'. These forms in Lithuanian, however, seem to have developed after the split, since in older Lithuanian literature (16th century and onwards) they had not yet merged (e.g. ''naujamę́jame'' ʽin the new one' from ''*naujamén'' + ''*jamén''). In Lithuanian, the pronoun merged with the adjective having a modern (secondary) pronominal inflection; in Slavic, the pronoun merged with an adjective, having an ancient (primary) nominal inflection.
* Usage of the genitive case for the direct object of a negative verb. For example, Russian ', Lith. ''knygos neskaičiau'' 'I haven't read the book'.
Shared vocabulary
Some examples of words shared among most or all Balto-Slavic languages:
*
*léiˀpāˀ '
tilia
''Tilia'' is a genus of about 30 species of trees or bushes, native throughout most of the temperateness, temperate Northern Hemisphere. The tree is known as linden for the European species, and basswood for North American species. In Great Bri ...
' (linden tree): Lithuanian ''
líepa'', Old Prussian ''līpa'', Latvian ''
liẽpa'', Latgalian ''
līpa'', Common Slavic ''
*lipa'' (Old Church Slavonic ''
липа'', Russian ''
ли́па'', Polish ''
lipa'', Czech ''
lípa'')
*
*ránkāˀ 'hand': Lithuanian ''
rankà'', Old Prussian ''rānkan'' (
acc. sg.), Latvian ''
rùoka'', Latgalian ''
rūka'', Common Slavic ''
*rǭkà'' (Old Church Slavonic ''
рѫка'', Russian ''
рука́'', Polish ''
ręka'', Czech ''
ruka'')
*
*galˀwā́ˀ 'head': Lithuanian ''
galvà'', Old Prussian ''
galwo'', Latvian ''
gal̂va'', Latgalian ''
golva''; Common Slavic ''
*golvà'' (Old Church Slavonic ''
глава'', Russian ''
голова́'', Polish ''
głowa'', Czech ''
hlava'',
Slavic ''
Triglav
Triglav (; ; ), with an elevation of , is the highest mountain in Slovenia and the highest peak of the Julian Alps. The mountain is the pre-eminent symbol of the Slovene nation, appearing on the Coat of arms of Slovenia, coat of arms and Flag ...
'' 'three-headed/three-faced' god).
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 and the southernmost dialects into Slavic (with Slavic later absorbing any intermediate idioms during its expansion). Andersen thinks that different neighboring and
substratum
Substrata, plural of substratum, may refer to:
*Earth's substrata, the geologic layering of the Earth
*''Hypokeimenon'', sometimes translated as ''substratum'', a concept in metaphysics
*Substrata (album), a 1997 ambient music album by Biosphere
* ...
languages might have contributed to the differences in basic vocabulary.
See also
*
Corded Ware culture
The Corded Ware culture comprises a broad archaeological horizon of Europe between – 2350 BC, thus from the Late Neolithic, through the Copper Age, and ending in the early Bronze Age. Corded Ware culture encompassed a vast area, from t ...
*
International Workshop on Balto-Slavic Accentology
*
List of Balto-Slavic languages
*
Outline of Slavic history and culture
Notes
References
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* Thomas Olander's master's thesis on the existence of Balto-Slavic genetic node solely on the basis of accentological evidence
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Further reading
* .
* Matasović, Ranko. "Supstratne riječi u baltoslavenskim jezicima"
ubstratum words in Balto-Slavic ''Filologija'', br. 60 (2013): 75-102. https://hrcak.srce.hr/116920
* .
*
Pronk, Tijmen. “Balto-Slavic”. In: ''The Indo-European Language Family: A Phylogenetic Perspective''. Edited by Thomas Olander. Cambridge: Cambridge University Press, 2022. pp. 269–92. .
External links
Balto-Slavic Accentuation by Kortlandt; a very idiosyncratic approach to Balto-Slavic accentuation
* (Bernstein and Trubachev on the Balto-South-Slavic isoglosses)
Biennial International Workshop on Balto-Slavic Natural Language Processing
{{Authority control
Indo-European languages