Kushluk was a member of the Naiman tribe of Mongols, and he led the Naiman against Temujin and Khangai during his campaigns in 1206 when he formed the Mongol Empire. Kushluk fled to the Kara-Khitai Khanate after the Naiman were defeated, and Khan Yelu-Zhilugu of Kara-Khitai Khanate accepted him as one of his advisers. However, Kushluk usurped the throne and became the khan in 1211, with Yelu-Zhilugu dying in 1213, ending the line of Kara-Khitai khans. Kushluk fought against Temujin in 1218 when he chased him down, and his attempts to destroy Genghis' great tent failed. He was chased down to his settlement, where he was surrounded by Mangudai cavalrymen and killed by both swords and arrows.