who led the mongols into russia and conquered kiev
Mongol invasion of Rus' In mid-1238, Batu Khan devastated the Crimea and pacified Mordovia. In the winter of 1239, he sacked Chernigov and Pereyaslav. After many days of siege, the horde stormed Kiev in December 1240. Despite the resistance of Danylo of Halych, Batu Khan managed to take two of his principal cities, Halych and Volodymyr-Volynskyi. The Mongols then resolved to "reach the ultimate sea", where they could proceed no further, and invaded Hungary and Poland.