Ariq Böke
Perhaps more important than himself was the role of his family, the Toluids, in shaping the destinies of the Mongol Empire. Through his Nestorian Christian wife Sorghaghtani Beki, Tolui fathered Möngke, Kublai, Ariq Böke, and Hulagu. The first three of these would all go on to claim the title of Great Khan, while Hulagu founded the Ilkhanate and Kublai the Yuan dynasty of China. It was the rivalry between Tolui's own sons, Kublai and Ariq Böke, that fragmented the power of the empire and set the western khanates against each other in the Toluid Civil War between 1260 and 1264.