Gongsun Yan 公孫衍, alias Xishou 犀首 "rhino head", was a high minister in the state of Wei 魏 during the Warring States period 戰國 (5th cent.-221 BCE). He hailed from Yinjin 陰晉 (modern Huayin 華陰, Shaanxi) and found his first job as supreme commander (daliangzao 大良造) in the state of Qin 秦.
He soon returned to Wei where he was appointed general by King Hui 魏惠王 (better known as King Hui of Liang 梁惠王, r. 371-335). Based on the experience won in Qin he vehemently argued that the regional states had to fight commonly against the aggressive expansion politics of the state of Qin.
In 323 he contributed to the mutual acknowledgements of the rulers of Yan 燕, Zhao 趙, Zhongshan 中山, Han 韓 and Wei. He was opposed to Zhang Yi's 張儀 suggestion to create an east-west alliance with Qin and managed the dismission of Zhang by King Hui.
In 319 Gongsun Yan was appointed counsellor (xiang 相) of Wei. In this position he finally forged the alliance of Han, Zhao, Wei, Chu 楚 and Yan against Qin. The Lord of Yiqu 義渠君 was specially entrusted to attack the army of Qin from the rear. Yet the allies were defeated by the militarily superior army of Qin. Gongsun Yan was rewarded with the right to use the seals of counsellor of all five states.