Zhang Yan
Zhang Yan, originally Chu Yan, was the leader of a bandit group in the Taihang Mountains in 184. At some point he joined another bandit, Oxhorn Zhang, but Zhang was fatally wounded in a raid and died soon afterwards. His last act was to transfer his men over to Chu Yan, who took the name of Zhang to honor his patron. Zhang Yan went on to create a bandit confederacy known as the Black Mountain bandits that ravaged the neighboring commanderies of Changshan, Zhao, Zhongshan, Shangdang, and Henei. In 190 Zhang Yan had a loose alliance with Gongsun Zan against Yuan Shao. In 193 Yuan Shao attacked the Black Mountain bandits, forcing them off the southern hills and into the mountains. When Yuan Shao made his final attack on Gongsun Zan in 199, Zhang Yan tried to save him but failed. Zhang Yan surrendered to Cao Cao when he took over Ji Province in 205. He was made a general as well as a marquis.