Oleg of Novgorod (Slavic: Олег, Old Norse: Helgi) was a Varangian prince (or konung) who ruled all or part of the Rus' people during the early 10th century. He is credited with moving the capital of Rus' from Novgorod the Great to Kiev and, in doing so, he laid the foundation of the powerful state of Kievan Rus'. He also launched at least one attack on Constantinople, capital of the Byzantine Empire. According to East Slavic chronicles, Oleg was supreme ruler of the Rus' from 882 to 912.
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