Emperor Xian of Han
Upon seeing Liu Bei's growing power, Lü Bu became worried that Liu Bei would turn against him, so he launched a preemptive attack on Xiaopei. Liu Bei fled to the imperial capital, Xuchang, where he took shelter under Cao Cao, the warlord who had been controlling the Han central government since he had brought the figurehead Emperor Xian of Han to Xuchang in 196. Cao Cao welcomed Liu Bei warmly, used Emperor Xian's name to appoint him as the Governor of Yu Province, and put him in command of some troops. Liu Bei then returned to Xiaopei to keep an eye on Lü Bu.