Kublai Khan was the fourth son of Tulë and the grandson of Genghis Khan (c. 1165–1227), the founder of the Mongol Empire. Strong, brave, and intelligent, Kublai was Genghis's favorite grandson; he had accompanied his father, Tulë, in battles as a child. By the age of twelve he was a skilled horseman, and his reputation as a warrior grew as he became older. Kublai was seventeen when his father died.
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