Genghis Khan[note 4] (c.¿1158 - August 18, 1227), born Temüjin, was the founder and first Great Khan (Emperor) of the Mongol Empire, which became the largest contiguous empire in history after his death. He came to power by uniting many of the nomadic tribes of Northeast Asia, and, after being proclaimed the universal ruler of the Mongols, or Genghis Khan, he launched the Mongol invasions, which ultimately conquered most of Eurasia, reaching as far west as Poland and as far south as Egypt. His major campaigns include those against the Qara Khitai, Khwarezmia, and the Western Xia and Jin dynasties, and raids into medieval Georgia, the Kievan Rus', and Volga Bulgaria.