Old East Slavic
language (or a group of dialects) used by the East Slavs from the 7th or 8th century to the 13th or 14th century
AI overview
Old East Slavic was the language spoken by East Slavic peoples from roughly the 7th or 8th century through the 13th or 14th century. It matters because it is the ancestor of modern Russian, Ukrainian, and Belarusian, and studying it helps us understand how these languages developed and how East Slavic peoples communicated during the medieval period.
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Article
Old East Slavic (traditionally also Old Russian) was a language (or a group of dialects) used by the East Slavs from the 7th or 8th century to the 13th or 14th century, until it diverged into the Russian and Ruthenian languages. Ruthenian eventually evolved into the Belarusian, Rusyn, and Ukrainian languages.
Terminology