Battle of Yan Province The Battle of Yan Province was a battle fought between the warlords Cao Cao and Lü Bu for control of Yan Province ( covering present - day southwestern Shandong and eastern Henan ) in the late Eastern Han Dynasty . The battle lasted for at least one hundred days with an indecisive conclusion . Background . In 192 , remnants of the Yellow Turban rebels from Qing Province invaded Yan Province and occupied Dongping and Rencheng . Liu Dai , Inspector of Yan Province , wanted to attack the rebels but Bao Xin , Chancellor of Jibei , advised him against it . Liu Dai ignored Bao Xin ' s warning , engaged the rebels in battle , and was eventually defeated and killed . At that time , Cao Cao ' s advisor Chen Gong urged him to take control of Yan Province and secure it as a base for conquering other territories . Chen Gong volunteered to persuade Liu Dai ' s followers to join Cao Cao . Bao Xin , who was friendly towards Cao Cao , travelled to Dong Commandery ( southwest of present - day Puyang , Henan ) to invite Cao to be the new Inspector of Yan Province . Cao Cao then attacked the Yellow Turban rebels at Shouzhang but failed to defeat them . After that , Cao Cao reformed his army , enforced military rules more strictly , and used incentives to encourage his men . He recognized that the rebels did not have a stable flow of supplies , as they relied on plundering to sustain themselves . Hence , Cao Cao launched surprise attacks on the rebels , prevented them from pillaging , and achieving ultimate victory and forcing the rebels to retreat north . Cao Cao pursued the rebels and defeated them again at Jibei ( south of present - day Changqing District , Shandong ) . The rebels , numbering more than 300 , 000 , including 100 , 000 civilians , surrendered to Cao Cao . Cao reorganized the surrendered troops to form the Qingzhou Corps ( 青州兵 ) , while implementing the " tuntian " system for the people to provide for themselves and the military . In 193 , Cao Cao ' s father Cao Song was killed by Zhang Kai ( 張闓 ) , a subordinate of Tao Qian , Governor of Xu Province . In retaliation , Cao Cao launched an attack on Tao Qian , sweeping through Tao ' s lands and slaughtering thousands of Xu Province ' s population , including civilians . Tao Qian retreated to Tancheng ( 郯城 ) , where Cao Cao was unable to conquer the city and retreated after his army was running low on supplies . The following year , Cao Cao attacked Tao Qian again , conquering many counties in Langya and Donghai commanderies of Xu Province . Just then , Cao Cao ' s subordinates Zhang Miao and Chen Gong rebelled against him and aided Lü Bu in taking over his home base of Yan Province . Cao Cao then decided to abandon his campaign on Tao Qian and turn back to retake Yan Province . The battle . Cao Cao and Lü Bu ' s forces were locked in a stalemate for at least a hundred days , with Cao on the disadvantageous end . Eventually , Lü Bu abandoned his position because of a famine outbreak . Cao Cao then laid siege to Lü Bu at Juye , Puyang . Cao Cao ' s advisors Xun Yu and Cheng Yu defended the cities of Juancheng , Fan and Dong ' e , but this left only two counties with solid defenses , so Cao Cao led his army back . Lü Bu arrived and was unable to take Juancheng by siege so he went west and garrisoned Puyang . Lü Bu re - stationed his forces to the east at Shanyang . In battle , Lü Bu used his cavalry in the first clash of arms , charging towards Cao Cao ' s Qingzhou Corps . The Qingzhou Corps fled in terror and Cao ' s formations were in complete disarray . Cao Cao , seeing the confusion , quickly galloped ahead when a fire broke out , but he fell from his horse and burnt the palm of his left hand . Cao ' s army halted before they reached camp , because most of Cao ' s generals had not seen their lord and feared for his safety . Cao Cao then strained himself to rouse his men , ordering that siege weapons be prepared immediately so that they can besiege Lü Bu again . Zhang Miao followed Lü Bu and left his brother Zhang Chao ( 張超 ) , Administrator of Guangling , to take care of their family at Yongqiu . Cao Cao laid siege on Yongqiu for several months and eventually captured the city , killing Zhang Chao and his family . Zhang Miao pleaded for assistance from Yuan Shu but was rejected and killed by his soldiers . At the same time , a locust plague broke out , causing many to starve while some resorted to cannibalism . Lü Bu had also used up all his provisions , horse feed , and grain supplies so both sides were forced to withdraw . When Cao Cao later surrounded Lü Bu at Puyang , the influential Tian clan , who were initially on Lü ' s side , switched allegiance to Cao and allowed his forces to enter the city . Cao Cao set fire to the eastern gate as a sign that he had no intention of reversing course , thereupon he came under attack and was defeated . Some of Lü Bu ' s horsemen captured Cao Cao but were unaware of his identity . Cao Cao saw a man riding on a yellow horse and lied that the man was him , so Lü Bu ' s horsemen released him and chased the rider . Cao Cao then dashed through the burning eastern gate and escaped from Puyang . Within two years , Cao Cao was able to recapture all the cities in Yan Province and defeated Lü Bu at Juye . Lü Bu then fled eastwards to join Liu Bei , who had taken over Xu Province from Tao Qian . Aftermath . The Battle of Yan Province led to the subsequent Battle of Xiapi in 198 , when the allied forces of Cao Cao and Liu Bei launched an attack on Lü Bu in Xu Province . Lü Bu was executed on Cao Cao ' s order after his defeat . Modern references . The battle was featured as a stage in Koei ' s video game " Dynasty Warriors 5 : Xtreme Legends " called the " Battle of Yan Province " . In " Dynasty Warriors 7 " , the battle is part of the " Battle of Xu Province " , which has Lü Bu attacking Cao Cao ' s main camp . It should not be confused with the " Battle of Yan Province " , which deals with remnants of the Yellow Turban rebels .