Founding of Kievan Rus’
Also called: Kyivan Rus’
The Rus’, a branch of the Norsemen, settled at Novgorod around 862, and in 882 Oleg moved their centre to Kyiv, founding Kievan Rus’, a state of the Eastern Slavs.

Viktor Vasnetsov · Public domain · Source
Norsemen from Scandinavia (Varangians) travelled a trade route from the Baltic down the Dnipro to the Black Sea and Byzantium. The Primary Chronicle relates that Rurik became ruler of Novgorod in 862 and that his kinsman Oleg seized Kyiv in the south in 882 and made it his capital. Kievan Rus’, which they founded as rulers of the Eastern Slavs, is the root of today’s Ukraine, Russia and Belarus. Soon afterwards, in Silla, the revolt of Wonjong and Aeno broke out under Queen Jinseong (889).