Siege of Suiyang

The siege of Suiyang was a military campaign during the An Lushan rebellion, launched by the rebel Yan army to capture the city of Suiyang from forces loyal to the Tang dynasty. Although the battle was ultimately won by the Yan army, it suffered major attrition of manpower and time. The siege was noted for the Tang army's determination to fight to the last man, as well as the large-scale cannibalism practised by the defenders, who in this way were able to hold out longer.

The An Lushan rebellion began in December 755. By the end of 756, the rebel Yan army had captured most of northern China, which then included both Tang capitals, Chang'an and Luoyang, and was home to the majority of the empire's population. The Yangtze basin had thus become the main base of the Tang dynasty's war efforts. In January 757, the newly self-proclaimed Yan emperor An Qingxu ordered general Yin Ziqi [zh] (尹子奇) to join forces with general Yang Chaozong (楊朝宗) and besiege Suiyang (present-day Shangqiu, Henan). Suiyang was a city on the Tang-era course of the Grand Canal, sitting midway between the major cities Kaifeng and Xuzhou. The city, therefore, formed a major obstacle for the rebels on the route from the capitals to the southeastern coast, the breadbasket of the Tang dynasty.

The administrator of Suiyang Prefecture at the time, Xu Yuan [zh] (許遠), requested help from garrisons in neighbouring cities. At the time, Zhang Xun, formerly a county magistrate serving in the Tang government, was the leader of volunteer defenders in Yongqiu. The Tang had granted him the title deputy jiedushi of Henan but could not provide any reinforcement or logistic support. Zhang had held off a rebel siege on his city in the previous year. However, as cities in the area fell one by one, Zhang quickly realized that his position in Yongqiu was becoming untenable. Recognizing the strategic importance of Suiyang, he led 3,000 men to aid its defence, bringing the total number of defenders to 6,800. Once he arrived, Zhang Xun took over the military leadership of Suiyang. Yao Kun [zh] (姚誾), the county magistrate of Chengfu, also arrived to help lead the defence of Suiyang. Meanwhile, Yin Ziqi mustered a huge army (estimated at 130,000 men) and started besieging the city in late January.

The united army of Zhang Xun and Xu Yuan, around 6,800 men, prepared to defend Suiyang with their lives. Xu Yuan focused on supplies management and after-battle repairs. Zhang Xun, on the other hand, focused on battle tactics.

Despite daily attacks by the Yan army, the Tang soldiers did not give up. Zhang Xun's troops played the battle drums during the night, acting as if they were going to fight. Consequently, the Yan army was forced to stand on guard at night and suffered from lack of sleep. Eventually, some troops did not bother to put on their armour when they heard these battle drums and kept sleeping. After the Yan army lowered their defences, Zhang Xun sent a dozen generals, including the famed archer Nan Jiyun [zh] (南霽雲) and Lei Wanchun [zh] (雷萬春), to lead 50 cavalry each in an attack on the enemy camp. The ambush was successful, and 5,000 Yan troops were slaughtered.

Zhang Xun had long wanted to give Yan morale a significant blow, and the best way to do this would be to hurt or kill Yan general Yin Ziqi. However, Zhang Xun did not know what Yin Ziqi looked like, nor would he be in a mix of soldiers. Zhang Xun, therefore, turned to psychology. He ordered his troops to shoot weeds, instead of arrows, at a few enemy soldiers. When these soldiers noticed they were being hit by weeds and left unharmed, they were overjoyed. They promptly ran to Yin Ziqi to report that the Tang army had already run out of arrows. Zhang Xun noticed where the soldiers ran and ordered his best archer, Nan Jiyun, to shoot at Yin Ziqi. One such arrow hit Yin Ziqi in his left eye, throwing the Yan army instantly into chaos. The siege ended with the expected significant blow to Yan morale.

After 16 days of siege and ambush, the Yan army had reportedly already lost 20,000 men. Yin Ziqi decided his army was too tired to fight, so he ordered a temporary retreat to regroup. Two months later, Yin Ziqi returned to besiege Suiyang with an additional 20,000 fresh troops. He began the final and ultimately successful siege early in the seventh lunar month of 757, continuing it until the city fell four months later.

Originally, Xu Yuan had prepared for the upcoming battle by storing a year's food inside Suiyang. However, the district governor insisted that he share the ample food supply with other nearby fortresses, and hence, the food supply became much less than what Xu Yuan originally planned. By July, the Tang soldiers had fallen into a severe food shortage. Tang soldiers were given tiny daily rations of rice. If they wanted more food, they would need to settle for whatever animals, insects, and tree roots could be found in their vicinity.