Chen Gong
In 194, when Cao Cao was away on another campaign against Tao Qian, Zhang Miao's younger brother Zhang Chao (), along with Cao's subordinates Chen Gong, Xu Si () and Wang Kai (), started a rebellion against Cao in Yan Province. Chen Gong successfully persuaded Zhang Miao to rebel against Cao Cao as well and invite Lü Bu into Yan Province. Chen Gong led his men from Dong Commandery (東郡; around present-day Liaocheng, Shandong) eastward to meet Lü Bu and they occupied Puyang (濮陽; in present-day Puyang, Henan). Lü Bu was declared Governor of Yan Province (). The various commanderies and counties in Yan Province responded to Lü Bu's call and defected to his side, except for Juancheng, Dong'e and Fan counties, which still remained under Cao Cao's control.