Altostslawische

Altostslawische, in linguistic German literature commonly referred to as Old East Slavic, denotes the medieval stage of the East Slavic languages spoken in the lands of Kievan Rus and its successor states. It spans roughly from the 10th to the 14th centuries and serves as the direct ancestor of the modern East Slavic languages: Russian, Ukrainian and Belarusian, as well as the historical Ruthenian variety.

Geographically, Altostslawische covered the core areas of Kievan Rus, including parts of what are now Russia, Ukraine and Belarus. Within its territory, regional dialects existed, such as the Novgorod and Kyiv varieties, which gradually diverged over time. The language is primarily known from literary and documentary sources rather than continuous spoken records.

Linguistically, Old East Slavic was written in the Cyrillic script, with strong influence from Church Slavonic in liturgical and official texts. It was highly inflected, with a rich nominal and verbal system typical of East Slavic languages, including case-based noun declensions and verbal aspects. The grammar and lexicon show both vernacular development and the impact of ecclesiastical and administrative language on everyday usage.

Literary evidence for Altostslawische includes chronicles (notably the Primary Chronicle), religious manuscripts, legal documents, and translations from Church Slavonic. Over time, regional varieties hardened into the distinct East Slavic languages of the later medieval period, while Church Slavonic retained prestige as a liturgical language. The evolution from Altostslawische to Russian, Ukrainian and Belarusian marks a foundational period in the linguistic history of Eastern Europe.