Kievan Rus, the first east Slavic state, was a federation of tribes, known as the Rus, who settled in the Baltic region. It was founded c. 880 by the Viking ruler, Oleg, who came from Novgorod. It is thought that the Rus are the cultural ancestors of the Russian, Ukrainian and Belarussian people. Oleg extended his kingdom as far south as Kiev and to east of the Dnieper River valley. Here, he met resistance from the Khazars, who were finally conquered by Sviatoslav I, Grand Prince of Kiev, in 965. Sviatoslav I extended Kievan Rus into the Volga River valley and south to shores of the Black Sea. His son, Vladimir the Great, fortified Kievan Rus’s frontiers and converted to Christianity. Vladimir the Great’s son, and successor, Yaroslav the Wise, was involved in a dynastic dispute, resulting in the Battle of Kiev in 1036. The kingdom began its decline after his death.
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