Kublai Khan was the fifth Khagan (Great Khan) of the Mongol Empire (Ikh Mongol Uls), reigning from 1260 to 1294, although it was only nominally due to the division of the empire. 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 brother Ariq Böke in the Toluid Civil Warlasting until 1264. This episode marked the beginning of disunity in the empire.

Kublai's real power was limited to China and Mongolia, though as Khagan he still had influence in the Ilkhanate and, to a significantly lesser degree, in the Golden Horde.

If one counts the Mongol Empire at that time as a whole, his realm reached from the Pacific to the Black Sea, from Siberia to modern day Afghanistan – one fifth of the world's inhabited land area.

In 1271, Kublai established the Yuan dynasty, which ruled over present-day Mongolia, China, Korea, and some adjacent areas, and assumed the role ofEmperor of China.

By 1279, the Yuan forces had overcome the last resistance of the Southern Song dynasty, and Kublai became the first non-native Emperor to conquer all of China.