The founder of the Mogol empire, originally called Tamujin he adopted the title Genghis Khan, Emperor of all in 1206 after uniting under his command the nomadic Mongol tribes of the Siberian steppes and destroying Tatar power. Organizing his horsemen into highly mobile and disciplined squadrons called ordus (hence 'hordes'), he attacked China's frontiers. Although his armies breached the Great Wall and captured Peking, they failed to conquer China completely. Advancing westwards, Genghis, by ruthless massacres, crushed all resistance in Afghanistan, Persia, and Southern Russia.
After his death his son Ogadai (1185-1241) executed Genghis' plan for the empire's organization.