The Proto-Slavic language existed until around AD 500. By the 7th century, it had broken apart into large dialectal zones. There are no reliable hypotheses about the nature of the subsequent breakups of West and South Slavic. East Slavic is generally thought to converge to one Old East Slavic language of Kievan Rus, which existed until at least the 12th century.
The Proto-Slavic language existed until around AD 500. By the. 7th century, it had broken apart into large dialectal zones. There are no reliable hypotheses about the nature of the subsequent breakups of West and South Slavic. East Slavic is generally thought to converge to one Old East Slavic language of Kievan Rus, which existed until at least the 12th century