"In 1259, the great Mongol Empire — which stretched from parts of China west to Russia — was shaken for the second time by the death of its leader, or khan, when Möngke, a grandson of the founder Genghis Khan, died. One of his brothers, Kublai, left his army in China, came back to Mongolia, and had himself declared the Great Khan." - Maitani from Bookmarklet

"When he took the throne, Kublai was in his forties. He was the fourth son of the fourth son of Genghis and had only about a decade’s experience in military and political leadership. But he proved his worth and justified the name given him by Mongols, Setsen Khan, or “the Wise Khan.”" - Maitani