of Yi Province. In 215 Sun Quan demanded that Liu Bei give him all of southern Jing Province that Liu Bei had obtained. When Liu Bei denied his demands, Sun Quan sent an invasion force commanded by Lü Meng and Lu Su and Liu Bei sent Guan Yu to confront the two in response while he gathers troops for an inevitable battle. A settlement was eventual reached, dividing southern Jing along the Xiang River. In 217 Liu Bei invaded Hanzhong Commandery, which was then under the control of Cao Cao, and solidified his gains in 219 by achieving a decisive victory over the Cao army and killing Xiahou Yuan. In the autumn of 219, Liu Bei proclaimed himself King of Hanzhong at a coronation ceremony in Mianyang, and established a court in Chengdu. Liu Bei's general, Guan Yu, besieged Fan city, in modern Xiangfan, but Cao Cao's cousin Cao Ren held out and Cao Cao's officer Xu Huang came to his rescue and drove Guan Yu away from Fan Castle. In the winter while Guan Yu was fighting against Cao Ren an offensive by Lü Meng into Nan Commandery ruined Guan Yu's position and he was killed by Lu Meng upon his capture. Sun Quan thus had seized all of Jing Province. On 15 May 221, Liu Bei proclaimed himself emperor. He then attacked Sun Quan through the Three Gorges and into the middle Changjiang. The following year Lu Xun destroyed Liu Bei's line of camps and forced him to retreat to Baidi Castle with heavy losses. Liu Bei fell ill soon after the battle and upon Sun Quan being under attack by the forces of Cao Pi the two reformed their alliance. Liu Bei died in the summer of 223 and was succeeded by his son Liu Shan, though the government was effectively under the control of Zhuge Liang as a part of Liu Bei's dying request. Liu Shan Liu Shan was only 17 years old when his father died and lacked the ability to lead so Zhuge Liang became de facto head of state. In 224 and 225 Zhuge Liang embarked on a Southern Campaign which brought at least nominal submission from chieftains in the south of Yi Province. In the north Zhuge Liang made several attempts to break through the Qinling range, managing to occupy Wudu Commandery in 229. However he was unable to press farther north