Genghis Khan died in 1227 while his armies were attacking Western Xia. His successor, Ögedei Khan, invaded the Jin dynasty again in 1232 with assistance from the Southern Song dynasty. The Jurchens tried to resist; but when the Mongols besieged Kaifeng in 1233, Emperor Aizong fled south to the city of Caizhou. A Song–Mongol allied army surrounded the capital, and the next year Emperor Aizong committed suicide by hanging himself to avoid being captured in the Mongols besieged Caizhou, ending the Jin dynasty in 1234. The territory of the Jin dynasty was to be divided between the Mongols and the Song dynasty. However, due to lingering territorial disputes, the Song dynasty and the Mongols eventually went to war with one another over these territories.
In Empire of The Steppes, René Grousset reports that the Mongols were always amazed at the valour of the Jurchen warriors, who held out until seven years after the death of Genghis Khan.