He was selected as the supreme khan in 1229 because of the kuriltai, the meeting for important leaders, was held after Genghis' death, but it was never doubted that Genghis wanted Ögedei to rule after him. During his reign, the Mongols ended the Jin Dynasty (in 1234) and fought against the Southern Song Empire. In 1235, under the khan's direct command, the Mongols began a war of conquest that would not end for forty-five years, and would result in the addition of all of China. Mongol armies established permanent control of Persia (commanded by Chormagan) and expanded westward under the command of Batu Khan to take over Russia.