Slavic third palatalization

The Proto-Slavic language, the hypothetical ancestor of the modern-day Slavic languages, developed from the ancestral Proto-Balto-Slavic language (c. 1500 BC), which is the parent language of the Balto-Slavic languages (both the Slavic and Baltic languages, e.g. Latvian and Lithuanian). The first 2,000 years or so consist of the pre-Slavic era, a long period during which none of the later dialectal differences between Slavic languages had yet happened. The last stage in which the language remained without internal differences that later characterize different Slavic languages can be dated around AD 500 and is sometimes termed Proto-Slavic proper or Early Common Slavic. Following this is the Common Slavic period (c. 500–1000), during which the first dialectal differences appeared but the entire Slavic-speaking area continued to function as a single language, with sound changes tending to spread throughout the entire area. By around 1000, the area had broken up into separate East Slavic, West Slavic and South Slavic languages, and in the following centuries it broke up further into the various modern Slavic languages of which the following are extant: Belarusian, Russian, Rusyn and Ukrainian in the East; Czech, Slovak, Polish, Kashubian and the Sorbian languages in the West, and Bulgarian, Macedonian, Serbo-Croatian and Slovenian in the South.

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