Answer:
Genghis Khan 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. After founding the Empire and being proclaimed Genghis Khan, he launched the Mongol invasions that conquered most of Eurasia, reaching as far west as Poland and the Levant in the Middle East.