Kuchlug (also spelled Küchlüg, Küçlüg, Güčülüg) was a member of the Naiman tribe of western Mongolia. He was defeated by Genghis Khan and fled westward to the Kara-Khitan Khanate, where he became an advisor. In 1210, he took control of the khanate. He was killed by the Mongols when they conquered the region in 1218.
Read more about Kuchlug: Naiman Origins and Westward Flight, Kara-Khitan Empire, Downfall and Death, In Popular Culture