Tautvilas or Tautvila (died in 1263) was Duke of Polatsk and one of the sons of Dausprungas and nephews of King of Lithuania Mindaugas. Tautvilas together with his brother Edivydas and uncle Vykintas waged a civil war against Mindaugas. The war resulted in coronation of Mindaugas. In 1248, Mindaugas sent Tautvilas, Edivydas, and Vykintas to conquer Smolensk promising that they could keep what they would conquer. Wikipedia
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