Chengjia (Chinese: 成家; 25–36 AD), also called the Cheng dynasty or Great Cheng, was a self-proclaimed empire established by Gongsun Shu in 25 AD after the collapse of the Xin dynasty of Chinese history, rivalling the Eastern Han dynasty founded by Emperor Guangwu later in the same year. Based in the Sichuan Basin with its capital at Chengdu, Chengjia covered a large area including modern Sichuan, Chongqing, Guizhou, Yunnan, and southern Shaanxi, and comprised about 7% of China's population at the time. Chengjia was the most dangerous rival to the Eastern Han, and was the last separatist regime in China to be conquered by the latter, in 36 AD.