Battle of the Sit River
The Battle of the Sit River, which occurred in the midst of the Mongol invasion of Russia on March 4, 1238, was fought in the northern part of the current Yaroslavl Oblast between the Mongol hordes of Batu Khan and the Russians under the leadership of George II of Vladimir-Suzdal. After the Mongols captured their capital in Vladimir, George escaped to the Volga to Yaroslavl, where he met him and joined his army. His forces were completely destroyed and along with his nephew, the prince Vsevolod of Yaroslavl, passed away. The Battle of the Sit River marked the end of the unified Russian resistance to the Mongols until Dmitri Donskoy, inaugurating two and a half centuries of Mongol domination over Russia.
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