May 31, 1223

The Mongols defeat the Rus' and Cumans at the Kalka

On 31 May 1223 Jebe and Subutai, after riding through the Caucasus and beating the Cumans, defeat the Rus' princes and Cumans at the Kalka River. The raid covers some 8,900 km in three years. Subutai returns with Batu in 1237 and conquers Kievan Rus'.