Li Guang
Li Guang committed suicide shortly after the Battle of Mobei in 119 BC. He was blamed for failing to arrive at the battlefield in time (after getting lost in the desert), creating a gap in the encirclement and allowing Ichise Chanyu to escape after a confrontation between Wei Qing and the Chanyu's main force, which the Han army narrowly managed to defeat. Refusing to accept the humiliation of a court martial, Li Guang took his own life.