Bei Yan was a military general serving under the warlord Gongsun Yuan during the Three Kingdoms period of Chinese history.
During the Liaodong campaign against Gongsun Yuan by the state of Cao Wei, Bei led Gongsun's troops against Sima Yi but ultimately lost. After he retreated from defeat, he once again reassembled his forces and attempted a second attack under Gongsun Yuan's order to fight to the death, but after several skirmishes, he was defeated and presumably slain.
Read more about Bei Yan: In Fiction