Cao Cao's forces thought that there was an ambush inside Zhao Yun's camp so they withdrew. Just as they were retreating, Zhao Yun launched a counterattack and his men beat the war drums loudly and fired arrows at the enemy. Cao Cao's soldiers were shocked and thrown into disarray. Some of them trampled on each other as they panicked and fled, while many of them fell into the Han River and drowned. The following day, when Liu Bei came to inspect Zhao Yun's camp and survey the battlefield, he remarked: "Zilong is full of courage." He then threw a feast to celebrate Zhao Yun's victory and they made merry until nightfall. Zhao Yun was also given the nickname "General of Tiger's Might" (). In late 219, Sun Quan broke the Sun–Liu alliance by sending his general Lü Meng to launch a stealth invasion of Liu Bei's territories in southern Jing Province while Guan Yu was away at the Battle of Fancheng against Cao Cao's forces. Guan Yu was later captured in an ambush and executed on Sun Quan's order when he refused to surrender. Following Cao Cao's death in March 220, his son and successor Cao Pi usurped the throne from Emperor Xian later that year, ended the Eastern Han dynasty, and established the state of Wei with himself as the new emperor. In 221, Liu Bei declared himself emperor and founded the state of Shu to challenge Wei's legitimacy. In the same year, Sun Quan pledged allegiance to Cao Pi and agreed to become a vassal under Wei; in return, Cao Pi granted him the title "King of Wu". Liu Bei bore a grudge against Sun Quan for the loss of Jing Province and wanted to attack Sun Quan. Zhao Yun attempted to dissuade him by saying:   Liu Bei ignored Zhao Yun's advice and proceeded with his quest for vengeance by personally leading a military campaign against Sun Quan. He left Zhao Yun behind to guard Jiangzhou (江州; in present-day Chongqing). In October 222, Liu Bei suffered a devastating defeat at the Battle of Xiaoting against Sun Quan's forces, and was forced to retreat to Baidicheng in Yong'an (永安; present-day Fengjie County, Chongqing). By the time Zhao Yun showed up with reinforcements at Yong'an, Sun Quan's forces had given up on pursuing Liu Bei and retreated back to Wu. After Liu Bei died in June 223, his son Liu Shan succeeded him as the emperor of Shu, with the Imperial Chancellor Zhuge Liang serving as regent because Liu Shan was still underage at the time.