Collected Illustrations of the Three Realms (Volume 27)

Zhang Yong, whose courtesy name was Fuzhi and who styled himself Guaiya original: 乖崖 (Guaiya), literally "The Eccentric Precipice", was a native of Juancheng. At the beginning of the Dazhong Xiangfu era 1008–1016 CE, a period of the Northern Song Dynasty, he presented bold and opposing arguments against the treacherous ministers Ding Wei and Wang Qinruo. As a result, he was sent out from the capital to serve as the Governor of Chen Prefecture.

Not long after, he passed away at the age of seventy. He was posthumously conferred the title of Vice Director of the Left Zuo Pushe: a high-ranking executive position within the Department of State Affairs and given the posthumous name Zhongding original: 忠定 (Zhongding), meaning "Loyal and Settled".

Emperor Zhenzong the third emperor of the Song Dynasty once praised his talents, remarking that Zhang possessed the caliber of a great military commander; however, due to Zhang's persistent illness, the Emperor was unable to make full use of his abilities in service to the state. Zhang once remarked of himself:

For this reason, he styled himself with the name Guaiya.