By the early 3rd century AD, the Han dynasty, now nearly four centuries old, was crumbling. Emperor
Xian, who acceded to the throne in 189 at age eight, was a political figurehead with no control over the regional warlords. Cao Cao was one of the most powerful warlords. He hosted the emperor in his capital at
Ye, which gave him a measure of control over the emperor in addition to an air of legitimacy. In 200 he had defeated his main rival
Yuan Shao at
Guandu,
reunifying northern China and giving him control of the
North China Plain. In the winter of 207 he secured his northern flank by defeating the
Wuhuan people at the
Battle of White Wolf Mountain. Upon returning to Ye in 208, Cao Cao was appointed
Chancellor upon his own recommendation, which effectively gave him control of the imperial government. Cao Cao's southern campaign started shortly after in the autumn of 208. The section of the Yangtze flowing through
Jing Province was the first target; capturing the naval base at
Jiangling and securing naval control of the province's stretch of the Yangtze were necessary to secure access to the south. He was opposed by the warlords
Liu Biao and
Sun Quan. Liu Biao, the governor of Jing, controlled the Yangtze west of the
Han River's mouth, which roughly encompassed the territory around the city of
Xiakou and to the south. Sun Quan controlled the Yangtze east of the Han and the southeastern territories abutting it.
Liu Bei, another warlord, was in
Fancheng, having fled to Liu Biao from the northeast after a failed plot to assassinate Cao Cao and restore imperial power. Initially, Cao Cao achieved rapid success. Jing was in a poor state. Its armies were exhausted by conflict with Sun Quan to the south. Furthermore, there was political division as Liu Biao's sons, the elder Liu Qi and the younger
Liu Cong, sought to succeed their father. Liu Cong prevailed, and Liu Qi was relegated to the
commandery of
Jiangxia. Liu Biao died of illness only a few weeks later. Liu Cong surrendered to an advancing Cao Cao, giving him a sizeable fleet and Jiangling as a forward operating base. Cao Cao's advance forced Liu Bei into a disorganised southward retreat accompanied by refugees and pursued by Cao Cao's elite cavalry. Liu Bei was surrounded and decisively defeated at the
Battle of Changban but escaped eastward to Xiakou, where he liaised with Sun Quan's emissary
Lu Su. Historical accounts are inconsistent: Lu Su may have successfully encouraged Liu Bei to move further east to Fankou (, near present-day
Ezhou, Hubei). In any case, Liu Bei was later joined by Liu Qi and levies from Jiangxia. Liu Bei's main advisor,
Zhuge Liang, was sent to Chaisang , present-day
Jiujiang, Jiangxi, to negotiate an alliance with Sun Quan against Cao Cao. Zhuge Liang told Sun Quan that Liu Bei and Liu Qi each had 10,000 men; these numbers may have been exaggerated, but however large a force the pair fielded was no match against Cao Cao's in an open battle. Sun Quan received a letter from Cao Cao prior to Zhuge Liang's arrival; in it, Cao Cao claimed to have an army of 800,000 and hinted that he wanted Sun Quan to surrender.
Zhang Zhao, Sun Quan's chief clerk, supported surrendering based on the disparity in forces. Zhuge Liang was supported by Lu Su and
Zhou Yu, Sun Quan's chief commander. Sun Quan agreed to the alliance; he chopped off a corner of his desk during an assembly and stated, "Anyone who still dares argue for surrender will be [treated] the same as this desk." Zhou Yu,
Cheng Pu, and Lu Su were assigned 30,000 men and sent to aid Liu Bei. With Liu Bei's 20,000 soldiers, the alliance had approximately 50,000 marines who were trained and prepared for battle. Zhou Yu estimated Cao Cao's strength to be closer to 230,000. This included between 70 and 80 thousand men
impressed from Ying, and whose morale and loyalty to Cao Cao were uncertain. Cao Cao's invasion force also included non-combatants: not only those who worked in supplies and communication, but also the wives and children of some of the soldiers. == Battle ==