Eastern Wu campaign against Cao Wei (241)

The Eastern Wu campaign against Cao Wei was a military offensive launched in 241 by the state of Eastern Wu against its rival state, Cao Wei, during the Three Kingdoms period in China. The campaign was initiated by Wu's founding emperor, Sun Quan, two years after the death of the second Wei emperor, Cao Rui. The campaign ended in overall failure.

Opening moves
In the spring of 241, when Sun Quan was preparing for an offensive on Wei, Yin Zha (殷札), the Administrator of the Wu-controlled Lingling Commandery (零陵郡; present-day Lingling District, Yongzhou, Hunan), advised him to attack Wei in coordination with Wu's ally state, Shu Han. According to Yin Zha's suggested plan, the Shu forces would attack Wei from the west of Chang'an, while the Wu forces would attack Wei from three directions: Zhuge Jin and Zhu Ran to attack Xiangyang Commandery (襄陽郡; present-day Xiangyang, Hubei); Lu Xun and Zhu Huan to attack Shouchun Commandery (壽春郡; present-day Shou County, Lu'an, Anhui); Sun Quan to attack the Huaiyang (淮陽) region and enter Xu Province. Yin Zha explaned that this coordinated campaign would wear down Wei's defences because they were unable to fend off attacks from different fronts. However, Sun Quan did not follow his plan.

The campaign
In the fourth lunar month, Wu forces attacked Wei at four different locations: Quan Cong attacked the Huainan region and clashed with Wei forces at Quebei (芍陂; south of present-day Shou County, Lu'an, Anhui); Zhuge Ke attacked Lu'an; Zhu Ran attacked Fancheng (樊城; present-day Fancheng District, Xiangyang, Hubei); Zhuge Jin attacked Zuzhong (柤中; in present-day Xiangyang, Hubei). On the Wei side, Wang Ling and Sun Li led troops to resist Quan Cong at Quebei, defeated him, and drove him back. Hu Zhi (胡質) also led lightly-armed forces from Jing Province to reinforce Fancheng. Someone warned Hu Zhi that the Wu forces attacking Fancheng had superiority in numbers and advised him to refrain from resisting them. However, Hu Zhi said, "The defences at Fancheng are weak. We should advance there to reinforce them, or else there will be big trouble." Having said that, he led his troops to Fancheng and restored stability in Fancheng.

Even after Hu Zhi reinforced Fancheng, the Wu forces did not withdraw from Jing Province. The Wei regent Sima Yi heard about it and requested for permission to further strengthen the defences at Fancheng because he foresaw that the loss of Fancheng would place Wei in a dangerous position. In the sixth lunar month, when the Wu forces received news of Sima Yi's arrival at Fancheng, they retreated at night but Sima Yi ordered his troops to give chase. The Wei forces caught up with the Wu forces at Sanzhoukou (三州口; at the intersection of the Bai, Tang and Han rivers in present-day Xiangzhou District, Xiangyang, Hubei), defeated them, and returned.

Aftermath
Lü Ju, Lü Fan's son, was promoted to the position of Lieutenant-General (偏將軍) for his contributions in the campaign.

In the intercalary month, Zhuge Jin died and his marquis title was passed on to his son, Zhuge Rong (諸葛融), who also inherited his father's military appointment and was stationed at Gong'an (公安; present-day Gong'an County, Jingzhou, Hubei). Zhuge Jin's title was not passed on to his eldest son, Zhuge Ke, because the latter already held a marquis title of his own. Two years later, in 243, Zhuge Ke sent spies to scout the strategic locations in Shouchun Commandery (壽春郡; present-day Shou County, Lu'an, Anhui) in preparation for an attack on the commandery. Sima Yi led troops to Shu County (舒縣; present-day Shucheng County, Lu'an, Anhui) as a defensive move against Zhuge Ke. Sun Quan eventually had Zhuge Ke relocated to Chaisang Commandery (柴桑郡; near present-day Jiujiang, Jiangxi).

After successfully repelling the Wu invasion, the Wei imperial court wanted to promote agriculture and build up an abundant stockpile of food supplies in Yang and Yu provinces in preparation for a future campaign against Wu. Deng Ai was sent to survey the lands in the Huainan region from Chen Commandery (陳郡; around present-day Zhoukou, Henan) east to Shouchun Commandery, and he proposed constructing a series of canals to irrigate the lands. Sima Yi approved Deng Ai's plan. The project commenced in the following year and helped to resolve not only food shortages but also flooding problems once it was in place.