Li Su

Li Su (; 773–821), courtesy name Yuanzhi , posthumous name Duke Wu of Liang , was a Chinese military general and politician of the Tang dynasty. He was most well-known for his surprise attack on Cai Prefecture (蔡州; in modern-day Zhumadian, Henan), then held by the warlord Wu Yuanji, successfully capturing Wu.

Background Li Su was born in 773, during the reign of Emperor Daizong. His father was Li Sheng, who would later rise to prominence as a major general during the reign of Emperor Daizong's son Emperor Dezong. When Li Su was young, on account of his father's accomplishments, he was first made Xielü Lang , a low-level official in charge of music at the ministry of worship (太常寺, Taichang Si), and later the deputy minister of army supplies (衛尉少卿, Weiwei Shaoqing). His birth mother died early, so he was raised by another concubine of Li Sheng's, Lady Wang, who was created the Lady of Jin. When Lady Wang died, Li Sheng, because she was not his wife, did not have Li Su observe the mourning rites for a mother, but Li Su tearfully requested to be allowed to observe those rituals, and Li Sheng agreed.

After Li Sheng died in 793, Li Su and his brother Li Xian built a tent next to Li Sheng's tomb, intending to observe the mourning period there. Emperor Dezong, believing the conditions were too harsh, ordered them to return to their own mansion, but after they went home for one night, the next day they were at the tomb again, and Emperor Dezong allowed them to continue to observe the mourning period there. After the mourning period was over, Li Su was made a member of the staff of Li Song the Crown Prince. He later served successively as the prefect of Fang (坊州, in modern Yan'an, Shaanxi) and then Jin (晉州, in modern Linfen, Shanxi) Prefectures, and was given the honorary title Jinzi Guanglu Daifu on account of his virtues. He later was recalled to again serve on the Crown Prince's staff, and later served as the head of the Crown Prince's household.

During Emperor Xianzong's reign

During the campaign against Wu Yuanji It was said that Li Su was full of strategies and capable in horsemanship and archery. In 816, during the reign of Emperor Dezong's grandson Emperor Xianzong, imperial troops were conducting a campaign against the warlord Wu Yuanji, who controlled Zhangyi Circuit (彰義, headquartered in modern Zhumadian, Henan)) without imperial approval, two successive imperial generals put in command of nearby Tangsuideng Circuit (唐隨鄧, headquartered in modern Zhumadian) — Gao Xiayu and Yuan Zi — had suffered defeats by Zhangyi troops. Li Su volunteered to serve in the campaign, and the chancellor Li Fengji also knew of Li Su's abilities, and therefore recommended him.

When Li Su reached the front in spring 817, it was said that the Tangsuideng soldiers, having suffered many defeats, were fearful of war. Li Su first comforted them by stating that his intentions were not to engage in battles immediately, and further personally attended to the wounded, to try to raise the morale. He also acted as if he was not taking military discipline seriously and not taking precautions toward Zhangyi troops, in order to get Zhangyi's guards down toward him. With Li Su not being well-known and the Zhangyi troops having just defeated Gao and Yuan, Zhangyi did not take particular precautions toward Li Su.

Li Su, meanwhile, requested and received reinforcements from several circuits. He then began to carry out military actions in which he targeted Zhangyi officers, captured them, and then treated them well and incorporated them into his command structure, using their familiarity with Zhangyi's defenses against Zhangyi. Such Zhangyi officers he thus captured included Ding Shiliang , Chen Guangqia , Wu Xiulin , Li Xian (李憲, whose name Li Su changed to Li Zhongyi , and Li You. His soldiers were particularly displeased at his endearment of Li You, pointing out that Li You had killed many imperial soldiers, and further accused Li You of being an agent of Wu. Li Su, in order to calm the soldiers, delivered Li You to Chang'an, ostensibly for Emperor Xianzong to execute him — and instead sent a secret petition to Emperor Xianzong, stating that he could not succeed if Li You were executed. Emperor Xianzong thereafter pardoned Li You and delivered him back to Li Su. Li Su further abolished the former orders that those who took in Zhangyi spies would be executed — instead ordering his people that if Zhangyi spies arrived, they were to be treated with kindness. As a result, the Zhangyi spies were turned toward Li Su and informed him about the status of Zhangyi troops. at dusk, Li Su launched the attack, from his then-base of Wencheng Fence (文成柵, in modern Zhumadian), without informing anyone other than Li You and Li Zhongyi what the intended target was. He had Li You and Li Zhongyi command the 3,000 Tujiang soldiers as first stage troops, with himself and the eunuch monitor of the army commanding 3,000 soldiers as the second stage troops and the officer Li Jincheng commanding 3,000 soldiers as the third stage troops. He attacked the village Zhangchai and killed the Zhangyi soldiers stationed there, and then, with 500 soldiers requisitioned from Yicheng Circuit (義成, headquartered in modern Anyang, Henan) remaining there to block off potential aid troops from Langshan and Ding commanding 500 soldiers to destroy bridges between Cai Prefecture and Huiqu, he continued to advance. After the soldiers had dinner, he announced that the target was Cai Prefecture itself — drawing much alarm from the officers and causing the eunuch monitor to cry bitterly, "We have fallen into Li You's trap!" At that time, there was a heavy snowstorm, such that Li Su's banner was torn, and some of his soldiers and horses were freezing to death, but he ordered continuing march forward. Li Shidao was thereafter killed by his own subordinate Liu Wu, who submitted to imperial authority.

During Emperor Muzong's reign In spring 820, Emperor Xianzong died and was succeeded by his son Emperor Muzong. Soon thereafter, Li Su was given the honorary chancellor title of Tong Zhongshu Menxia Pingzhangshi .

The soldiers all wept in sadness. Meanwhile, Niu Yuanyi the prefect of Shen Prefecture (深州, in modern Hengshui, Hebei), was not willing to follow Wang. Li Su, hearing this, sent his sword and jade belt to Niu, sending a message to him: "My father had used this sword to accomplish great things. I have also used this sword to capture Cai Prefecture. Now I give it to you, Lord, and you should use it to destroy Wang Tingcou." Niu was touched, and showed the sword and belt to his soldiers and stated, "I am willing to die for the empire." Li Su was then preparing an attack against Wang in conjunction with Niu, but suddenly fell ill again. Emperor Muzong thus made Tian Bu the military governor of Weibo to succeed him. and allowed to return to the eastern capital Luoyang to try to recover from illness. However, he died there in winter 821. He was buried with great honors.

Notes and references

Old Book of Tang, vol. 133. New Book of Tang, vol. 154. Zizhi Tongjian, vols. 239, 240, 241, 242, 243.