Сколько веков существовала Ки́евская Русь?
Kievan Rus' ( (), (), ) was a loose federation of East Slavic and Finnic peoples in Europe from the late 9th to the mid-13th century, under the reign of the Varangian Rurik dynasty. The modern nations of Belarus, Russia, and Ukraine all claim Kievan Rus' as their cultural ancestors, with Belarus and Russia deriving their names from it.
9th to the mid-13th century