egö dei at English => English (The Britannica Concise) Of Explained:
Son of Genghis Khan who succeeded his father in 1229 and greatly expanded the Mongol empire. He established his headquarters in central Mongolia and built the capital city of Karakorum. Like his father, he carried out simultaneous campaigns by relying on generals who acted independently but were subject to his orders. Allying himself with China's Southern Song dynasty, Ö gö dei attacked the Juchen Jin dynasty in N China, taking its capital in 1234. Meanwhile, his nephew Batu defeated Russia while other generals were attacking Iran and Iraq. Only Ö gö dei's death (during a drinking bout) prevented the invasion of Western Europe. See also Golden Horde, Kublai Khan, Mö ngke.