Battle of Guandu

The Battle of Guandu was fought between the warlords Cao Cao and Yuan Shao in 200 AD in the late Eastern Han dynasty. Cao Cao's decisive victory against Yuan Shao's numerically superior forces marked the turning point in their war. The victory was also the point at which Cao Cao became the dominant power in northern China, leading to the establishment of the state of Cao Wei in the Three Kingdoms period.

The inevitability of military conflict between Cao Cao and Yuan Shao had become apparent by 196. Yuan Shao held control of the lands north of the Yellow River, namely the Hebei region, while Cao Cao controlled most of the lands south of the Yellow River after he defeated Lü Bu at the Battle of Xiapi in 199 and kept Emperor Xian with him in the new capital city of Xu. The warlords saw each other as the obvious impediment to their individual ambitions to conquer and rule China.

Some years before the battle, Yuan Shao's advisors Ju Shou and Tian Feng warned that Cao Cao would become a threat to their lord in his ambition to dominate China. They advised Yuan Shao to attack Cao Cao when the latter was still building up his forces, but Yuan Shao ignored their advice as Cao Cao was still nominally an ally. Tension between Cao Cao and Yuan Shao increased after Cao Cao moved Emperor Xian from the old capital Luoyang.

The geographical position of Guandu (官渡; northeast of present-day Zhongmu County, Henan) made it a strategically vital position. It was near Yan Ford (延津; north of present-day Yanjin County, Henan) on the Yellow River and lay on the road leading to the capital city Xu. Cao Cao recognized its strategic importance and in the autumn of 199, he stationed troops there and prepared fortifications. Other deployments along the frontline included Liu Yan (劉延) at Boma (白馬; near present-day Hua County, Henan), Yu Jin at Yan Ford, Cheng Yu at Juancheng (鄄城; near present-day Juancheng County, Shandong), and Xiahou Dun at Meng Ford (孟津; present-day Mengjin County, Henan). At the same time, Cao Cao sent Zang Ba to harass Qing Province (青州), which was governed by Yuan Shao's son Yuan Tan, to prevent his eastern flank from coming under attack.

In the first month of 200, Liu Bei rebelled against Cao Cao and seized Xu Province after killing Che Zhou (車冑), Cao Cao's appointed Inspector (刺史) of Xu Province. Cao Cao, in an unexpected move, left his northern front exposed to Yuan Shao and turned east to retake Xu Province. Yuan Shao tried to use the opportunity to start a campaign south, but was daunted by Yu Jin, the defender of Yan Ford.

When Cao Cao returned to Guandu after his victory over Liu Bei, who sought refuge under Yuan Shao afterwards, Yuan Shao decided to renew the campaign against Cao Cao. The aide-de-camp (參軍) Tian Feng, who had urged Yuan Shao to attack Cao Cao while he was away, advised against such a campaign, reasoning that they had lost their chance and must wait. Yuan Shao ignored Tian Feng's repeated remonstrations and imprisoned him under charges of demoralizing the army.

Shortly after, Yuan Shao had Chen Lin draft a document condemning Cao Cao in what was essentially a declaration of war, and marched his main army toward the forward base of Liyang (黎陽; northwest of present-day Xun County, Henan) north of the river. At the time, Yuan Shao's army boasted of numbers up to 110,000, including 10,000 cavalry.

Yuan Shao's general Yan Liang crossed the Yellow River and besieged Cao Cao's fort at Boma. Heeding his advisor Xun You's advice, Cao Cao led a battalion toward Yan Ford as a feint to trick Yuan Shao into believing that Cao Cao would attack his camp on the other side of the river. Yuan Shao split off his troops from Liyang to counter Cao Cao's attack, leaving Yan Liang without any support at Boma. Cao Cao then struck eastward to lift the siege on Boma. In the ensuing battle, Yan Liang was killed by Guan Yu and Yuan Shao's army was routed.