Hengyang (; ) is the second largest city of Hunan Province, China. It straddles the Xiang River about south of the provincial capital of Changsha. As of the 2020 Chinese census, Its total population was 6,645,243 inhabitants, whom 1,290,715 lived in the built-up (or metro) area consisting of 4 urban districts, Nanyue District not being conurbated yet. Hengyang is home to University of South China, Hengyang Normal University, and Hunan Institute of Technology, three major provincial public universities in the city. History The former name of the city was Hengzhou (Hengchow) (). This was the capital of a prefecture in the Tang Dynasty's Jiangnan and West Jiangnan circuits. Li Jingxuan was banished to superintendence of Hengzhou after feigning an illness and attempting to usurp control of the legislative bureau at Chang'an against the Gaozong Emperor's wishes in AD 680. Following the AD 705 coup that removed the Empress Wu Zetian from power, her ally Li Jiongxiu was also briefly demoted to superintendence of this province. During the reign of Emperor Muzong, the chancellor Linghu Chu was also demoted to this province for his underlings' alleged corruption. In the 750s, the superintendent of Hengzhou Chen Xi'ang not only ruled his own region but also used his private army to dominate his nominal superior, the military governor Zhang Weiyi headquartered in Jing Prefecture (modern Jingzhou). Upon Zhang's replacement by the former chancellor Lü Yin in 760, however, Chen was placated and then killed in a surprise attack. During the reign of the Tang emperor Xizong, Zhou Yue overthrew first the prefect of Hengzhou Xu Hao in 881 and then the agent of the rebel Qin Zongquan in the capital of the Qinhua Circuit at Tan Prefecture (modern Changsha) in 886. Xizong confirmed Zhou Yue in all his posts, renaming his circuit Wu'an. Xizong's brother then gave him additional authority over West Lingnan Circuit (modern Guangxi). Shortly after, in 893, Deng Chune and Lei Man attacked and killed him. Other superintendents included Qi Ying and Xiao Ye. After initially falling to agrarian rebels under Yang Shiyuan, Hengzhou was recovered by the lord of Wu'an Ma Yin and formed part of his power base during the collapse of the Tang. He initially supported the Later Liang, then declared himself king (Ma Chu) in his own right during the Five Dynasties and Ten Kingdoms period. During the Revolt of the Three Feudatories, Wu Sangui declared