Genghis Khan united the Mongol and Turkic tribes of the steppes and became Great Khan in 1206. He and his successors expanded the Mongol empire across Asia. Under the reign of Genghis' third son, Ögedei Khan, the Mongols destroyed the weakened Jin dynasty in 1234, conquering most of northern China. Ögedei offered his nephew Kublai a position in Xingzhou, Hebei. Kublai was unable to read Chinese but had several Han Chinese teachers attached to him since his early years by his mother Sorghaghtani. He sought the counsel of Chinese Buddhist and Confucian advisers. Möngke Khan succeeded Ögedei's son, Güyük, as Great Khan in 1251. He granted his brother Kublai control over Mongol held territories in China. Kublai built schools for Confucian scholars, issued paper money, revived Chinese rituals, and endorsed policies that stimulated agricultural and commercial growth. He adopted as his capital city Kaiping in Inner Mongolia, later renamed Shangdu.