Külüg Khan , born Khayishan, was the Emperor of China and ruled as emperor of the Yuan Dynasty, khanate of Mongol Empire.
He was the eldest son of Darmabala and Dagi of the influential Khunggirad clan, and the full brother of . Since his uncle did not have the legitimate heir, he was considered a major candidate for the grand-khan. In 1299 he was sent to Mongolia to assume an army that defended the western front of the Yuan against Kaidu and other princes of Central Asia under him. In 1301 he defeated Kaidu, who died from a battle wound. In recognition of the great victory, Külüg Khan was given the title of Prince Huanning in 1304. In 1306 he forced Melig Temür to accept a surrender in the Altai Mountains. For these military achievements he gained a high reputation among Mongol princes and non-Mongol corps.
In 1307 when Temür Khan died, he returned eastward to Khara Khorum and watched the situation. Temür's widow Bulghan of the Bayaud tribe had kept away the Khunggirad-mothered brothers of Khayishan and Ayurbarwada and attempted to set up , a cousin of Temür. The Khunggirad faction arrested Ananda and Bulghan by coup and recalled Ayurbarwada and Dagi from Henan. Then Khayishan decided to hold the coronation ceremony in Shangdu just as his great-grandfather Khubilai Khan did, and advanced southward with the most part of his army. He was welcomed by Ayurbarwada, who gave up khanship, and ascended to the throne. He had executed Ananda and Bulghan before succession.
The Khayishan administration was founded on the unstable balance between Khayishan, his younger brother Ayurbarwada and their mother Dagi of the Khunggirad clan. Khayishan appointed Ayurbarwada as Crown Prince on the condition that he would pass the status to Khayishan's son after succession. He generously gave bonus to imperial princes and Mongol aristocrats, and enjoyed popularity among them. Meanwhile he was plagued by financial difficulties which was caused by free-spending policies and longstanding military spending. So he brought back the department of Shangshusheng for financial affairs in parallel with the Zhongshusheng for administrative affairs. He changed branch offices of Zhongshusheng to those of Shangshusheng to strengthen monopoly in salt and other goods. He issued new bills called Zhida-yinchao to replace Zhiyuan-chao. His anti-inflation plans did not achieve adequate results in his short reign, and dissatisfied Chinese officers and commoners.
He gave key posts to his retainers who had followed him since he had been stationed in Mongolia. He favored non-Mongol corps including the Kipchak, the Asud and the Qangl&. In contrast, he did not reward abundantly the Khunggirad faction who had carried out a coup against Bulghan.
In 1310, Kaidu's son Chapar, who tried to unsuccessfully overthrow Kebek, gave up to Khayishan, ending half-century lasted mongol civil war.
Immediately after Khayishan died and Ayurbarwada succeeded in 1311, the unsatisfactory Khunggirad faction came together under his mother Dagi and purged pro-Khayishan officials. It also broke Ayurbarwada's promise to appoint Khayishan's son as Crown Prince. It drove Khayishan's sons and out of the central government. Pro-Khayishan generals cherished grievances until they managed to set up Tugh Temür in 1323.