The title Khan became well known when the tribal Mongol TemÃ 1\/4 jin proved himself a military genius by creating the Mongol Empire , the greatest land empire the world ever saw , which he ruled as Genghis Khan . The title Khan became unprecedently prominent when the tribal Mongol TemÃ 1\/4 jin proved himself a military genius by creating the Mongol empire , the greatest land empire the world ever saw , which he ruled as Genghis Khan .