Kublai Khan Kublai Khan Kublai (; , "Hubilai"; Chinese: 忽必烈) was the fifth Khagan (Great Khan) of the Mongol Empire ("Ikh Mongol Uls"), reigning from 1260 to 1294 (although due to the division of the empire this was a nominal position). He also founded the Yuan dynasty in China as a conquest dynasty in 1271, and ruled as the first Yuan emperor until his death in 1294. Kublai was the fourth son of Tolui (his second son with Sorghaghtani Beki) and a grandson of Genghis Khan. He succeeded his older brother Möngke as Khagan in 1260, but had to defeat his younger
Mongol invasions of Vietnam repeatedly ignored demands to attend the Yuan court and offer his personal submission to the Great Khan. By 1266, a standoff developed, as the Emperor Thánh Tông sought a loose tributary relationship, while Kublai demanded full submission. Trần Thánh Tông sent an official letter requiring Kublai to take his darughachi back. Because of civil war in the Mongol Empire, and the Yuan conquest of Song China, armed conflict was delayed. Instead, Kublai reminded him of the peace treaty signed by the Mongols and Đại Việt. As a result of the Mongol conquest of the Song Empire, by 1278–79, Mongol troops