The Mongol invasion of Volga Bulgaria lasted from 1223 to 1236. The Bulgar state, centered in lower Volga and Kama, was the center of the fur trade in Eurasia throughout most of its history. Before the Mongol conquest, Russians of Novgorod and Vladimir repeatedly looted and attacked the area, thereby weakening the Bulgar state's economy and military power. The latter ambushed the Mongols in the later 1223 or in 1224. Several clashes occurred between 1229–1234, and the Mongol Empire conquered the Bulgars in 1236.
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Strengthening the power and strengthening the Tatar (Mongol) troops allowed Batu to move on to the task of capturing the Middle and Lower Volga. The Bulgars (Oghurs) lived on the Middle Volga, and the Lower Volga had always been under the Polovtsians (Kipchaks). The Arab author of the late 13th century Ibn Vasil reports:
Genghis Khan gave Jochi the task of continuing his conquests in Eastern Europe, but he evaded it. Then Genghis Khan sent Jebe and Subedei to Transcaucasia and the Black Sea steppes.
In 1222, the Polovtsians (Kipchaks) succumbed to the persuasion of the Tatars (Mongols) and broke their alliance with the Alans, after which the Tatar (Mongol) army invaded the Polovtsian steppes (Crimea, Azov, Caspian, Lower Volga) from the North Caucasus. The late Tver Chronicle reports on the reaction of Mstislav of Kiev to the news of the approach of the Tatar (Mongols) to the borders of Rus':