The Khan ruled the Mongols throughout the majority of its existence. The most well known of all the Khans was Genghis Khan who was the major leader in the massive expansion of their empire. Genghis Khan came to power in the late 1100's and at the time was still known as Temujin. He soon acquired the title of "Khan", and immediately used his power to create a large military force, which he used to expand the empire. Genghis Khan acted as the sole leader of the Mongol Government making their government a autocracy. When Genghis Khan passed in 1227 AD, his grandson Kublai Khan took over in control as the autocrat. He succeeded in the total capture of china and continued to expand the empire outwards.