Proto-Baltic language

The current Lithuanian and Latvian lands combined constitute approximately one-sixth of the former Baltic territory.

Russian philologist Vladimir Toporov believes that during 1000–800 BC Proto-Germanic people began expanding into the western Baltic territory starting from the Pasłęka River.

During the migration period Slavic people began expanding into the northern and eastern territories of the Balts.

[14] Since 1225, the conquests of the Teutonic Order in the current Baltic region intensified and later on resulted in the extinction of the Old Prussians in the 18th century.

[15] After a long-running debate in the 20th century about the exact nature of the relationship between the Baltic and Slavic branches of the Indo-European family, in the 21st century many historical linguists moved firmly in favour of a shared genealogical history between these two branches, both deriving from a common intermediate source, Proto-Balto-Slavic, after the breakup of Proto-Indo-European.

[28] Some similarities between Baltic and Slavic can be found on all levels of linguistic analysis, which led German philologist August Schleicher to believe that there was indeed a common point of development.

French linguist Antoine Meillet, however, rejected this idea and claimed that similarities between Baltic and Slavic languages were a result of close contact.

Meanwhile, Latvian linguist Jānis Endzelīns suggested that following the split of PIE, Baltic and Slavic languages evolved independently, but later experienced a common period of greater contact.

Jan Michał Rozwadowski proposed that the two language groups were indeed a unity after the division of Indo-European, but also suggested that after the two had divided into separate entities (Baltic and Slavic), they had posterior contact.

[29] Russian linguists Vladimir Toporov and Vyacheslav Ivanov believed that Proto-Slavic language formed from the peripheral-type Baltic dialects.

According to German linguist Wolfgang P. Schmid [de], at first Proto-Baltic was a centum language along with Proto-Germanic, but it eventually became satem later on.

[36] Both Baltic and Germanic emotional verbs possess similar semantic development, which is evinced by roots like *dhers- and *dreǵh-.

This semantic group is also noted for having exclusive isoglosses (e.g. PIE: *dreǵh-, *dherbh-, *u̯rengh-, *peḱ-), though they differ in meaning.

This is evinced by the possession of *-mo- (e.g. Lithuanian: pirmas, Gothic: fruma, Old English: forma), second consanguineous component (cf.

Lithuanian: vie-nuo-lika, dvy-lika, Gothic: ain-lif, twa-lif, Old High German: ein-lif, zwei-lif), identical dual number pronouns in first and second person (cf.

Lithuanian: sniegas drimba, Latvian: sniegs drēbj, Old Icelandic: drift snaer ‘snow is falling down’)[39] and resemblance of comparative degree prefixe -esnis to its corresponding Germanic counterpart (cf.

[46][47] Long mixed diphthongs, which position in the morpheme is hardly determined or their existence is questionable are presented in Italic: The consonants of Proto-Baltic experienced greater changes than primary vowels when in their primordial condition.

[48][49] The sonorants of PIE *ṛ, *ḷ, *ṃ, *ṇ, which were used as vowels and could form a syllable, turned into mixed diphthongs *ir, *il, *im, *in (in rarer cases—*ur, *ul, *um, *un) in Proto-Baltic.

These diphthongs alternated (had an ablaut) with *er (*ēr), *el (*ēl), *em (*ēm), *en (*ēn) and *ar (*ōr), *al (*ōl), *am (*ōm), *an (*ōn).

Masculine and feminine nouns of the same stem had identical endings, and the grammatical gender was indicated by gender-changing words (pronouns, adjectives, participles, etc.)

Because of the disappearance of the semivowel *i̯ between a consonant and a front vowel, neuter *i-stem words had changes *mari̯ī > *marī 'two seas', *aru̯i̯ī > *aru̯ī 'two suitable ones' in dual.

Unlike other parts of speech, the verb of Proto-Baltic experienced a lot of changes—the grammatical mood, tense and voice systems that came from PIE changed.

In Lithuanian, the relationship between the infinitive and dative can sometimes be observed to this day (e.g. kėdė yra sėdėti / sėdėjimui 'the chair is for sitting', ne metas liūdėti / liūdėjimui 'no time for sadness').

The participle had three genders (masculine, feminine and neuter), numbers (singular, dual, plural) and tenses (present, future, past).

There were two personal pronouns, they had no grammatical gender — *ež (*eš) 'I' and *tu / *tū 'you', which possessed suppletive inflexion forms preserved from PIE.

[76] Dutch Professor Frederik Kortlandt believed that only the oldest and non-renewed pronoun forms should be reconstructed in Proto-Baltic language while Lithuanian linguist-historian Professor Zigmas Zinkevičius believed older pronoun forms only existed at the earliest stages of Proto-Baltic.

Cardinal number 6 has three different reflexes in the Balto-Slavic languages: one in Latvian and pre-Lithuanian, another one in Old Prussian and a final one in Proto-Slavic.

[83] number *h₁óyneh₂ (f.) *h₁óynom (n.) *aiˀnāˀ *aiˀna *ainā *aina *dwóy(h₁) *duwai *d(u)u̯ai *uš?

[*šéš] (*sweš[84]) Proto-Western-Baltic *us [> PS *šȅstь] (> both PB *sešes and *us) (> variant *dewin) (> PS *dȅvętь) Numerals in Proto-Baltic, except for 'two', had noun endings: *ainas / *einas[85][86] (PIE: *h₁óynos) 'one' was inflected the same way as noun word stems o (masculine and neuter) and ā (feminine), this numeral had a singular, dual and plural number; masculine *d(u)u̯ō (PIE: *dwóh₁) and feminine-neuter *d(u)u̯ai (PIE: *dwóy(h₁)) 'two' was inflected as a demonstrative pronoun dual; *trii̯es (masc.

PIE: *tréyes) 'three' was inflected as a plural noun with the word stem i and was common for all genders; eventually, *ketures (masc.