Jiang Wei's Northern Expeditions - Seventh Expedition: Battle of Duan Valley

Seventh Expedition: Battle of Duan Valley

In 256, Jiang Wei had arranged for Hu Ji to assist his expedition aiming for Mount Qi. However, Hu Ji broke his promise and did not arrive as planned. When Jiang Wei heard that Deng Ai was fully prepared, he decided to attack Nan'an and left his Qishan camp with patrol decoys carrying his insignia. Deng Ai, who saw through the deception, left Chen Tai to attack Jiang's Qishan camp and made forced marches to Nan'an. Deng position his army at the peak of Mount Wucheng, an advantageous position to the city of Nan'an. Jiang Wei launched failed three sorties to take it. Later that evening, he consulted Xiahou Ba. Xiahou Ba told him to take Shanggui, Nan'an's grain depot, cutting Nan'an from supplies and let the city starve to death. Taking the Xiahou's advice, Jiang Wei led crack generals and troops to Shanggui via Duan Valley. However, Deng Ai was a step ahead of him. He send his son, Deng Zhong with his company of troops, lying in ambush at the same valley. As a result, Jiang Wei was badly defeated and suffered heavy casualties at Duan Valley. Xiahou Ba rescued Jiang Wei from the trap and reported to him that the Qishan camp has been overrun by Chen Tai and his troops. Due the destruction of the Qishan camp, Jiang Wei ordered his army to retreat to Hanzhong. Chen Tai ambushed and encircled Jiang Wei's fleeing army. Zhang Ni came to Jiang's aid to break the encirclement with cost of his own life. Jiang Wei petitioned to the Shu court to demoted him to Rear General for his defeat. It dealt him a major loss that would cause the Shu citizens resent his regency.