Fu Gongshi
Fu Gongshi was an agrarian rebel leader who served as Du Fuwei's lieutenant during the disintegration of the Chinese dynasty Sui Dynasty, who later followed Du in submitting to Tang Dynasty. In 623, while Du was at the Tang capital Chang'an, Fu rose against Tang rule at Danyang and declared himself emperor of a new state of Song. In 624, he was defeated by the Tang general Li Xiaogong. He fled, but was captured and delivered to Li Xiaogong, who executed him.
Initial uprising
Fu Gongshi was from Qi Province. He often stole sheep from his uncle to give to his best friend Du Fuwei, who was younger than he was, causing both of them to come to the attention of the police. They fled, and they became agrarian rebels against Sui Dynasty rule, in or briefly before 613. Du eventually became a major rebel leader, and Fu served as his lieutenant. In 613, it was Fu who, at Du's direction, persuaded another rebel leader, Miao Haichao, to submit to Du's leadership, and he also contributed to Du's subsequent surprise attack and killing of another rebel leader, Zhao Pochen.Submission to Tang
After the death of Emperor Yang of Sui in 618, Du Fuwei initially contended for supremacy of the lower Yangtze River region with fellow rebel leader Li Zitong the Emperor of Wu and the former Sui officials Shen Faxing the Prince of Liang and Chen Leng, but after he was defeated by Li in 619, he submitted to Tang Dynasty. Emperor Gaozu of Tang commissioned Du as the commandant of the region, and in summer 620, Emperor Gaozu created Du the Prince of Wu, bestowed on him the imperial surname of Li, and made him the head of the branch imperial government for the region, while creating Fu Gongshi the Duke of Shu and making him Du's deputy.Later that year, Li Fuwei commissioned Fu to lead an army against Li Zitong, with Li Fuwei's officers Wang Xiongdan and Kan Leng as Fu's assistants. Fu was quickly able to capture Danyang, and he had initial further battle successes against Li Zitong. However, after a Li Zitong counterattack, Fu stopped engaging Li Zitong. Wang, against Fu's orders, counterattacked himself and defeated Li Zitong, forcing him to flee and take over Shen's territory, while Li Zitong's former territory came under Li Fuwei's control.
Rebellion against Tang
Meanwhile, friction had been developing between Li Fuwei and Fu Gongshi. It had been that for years, the army, knowing the great friendship between Li Fuwei and Fu, honored Li Fuwei as its father and Fu as its "uncle." Eventually, however, Li Fuwei became suspicious of the respect the army had for Fu, and began to give more authorities to Wang Xiongdan and Kan Leng, giving them effective command of the army. When Fu realized that Li Fuwei was suspecting him, he became resentful, but pretended to lose interest in the army, instead studying alchemy with his friend Zuo Youxian.In 622, Li Fuwei, fearful that Emperor Gaozu might doubt his loyalty, went to the Tang capital Chang'an to pay homage to Emperor Gaozu, taking Kan with him. Before he departed, he left Fu in command, with Wang as Fu's deputy, in actual command of the forces, secretly warning Wang, "If I suffer no ill consequences, make sure that Fu does nothing rash." When Li Fuwei got to Chang'an, Emperor Gaozu gave him the special treatment of allowing him to sit with Emperor Gaozu on the imperial seat and, at other occasions, honor even above Emperor Gaozu's son Li Yuanji the Prince of Qi. However, he did not permit Li Fuwei or Kan to return to Danyang, making Kan a general.
Once Li Fuwei left Danyang, Zuo persuaded Fu into planning a rebellion. However, Wang had actual command of the army, and therefore, Fu decided to trick Wang by claiming that Li Fuwei was doubting Wang's loyalty. Wang, angry over the revelation, gave up command of the army, and Fu took control and then tried to persuade Wang to join his plot. Wang, realizing that he had been tricked, nevertheless refused to join Fu, so Fu strangled him. In fall 623, Fu, claiming that Li Fuwei had been detained by Emperor Gaozu and had ordered him to rebel, did so. He soon declared himself the Emperor of Song, and he was able to get another rebel leader who had submitted to Tang as well, Zhang Shan'an, who controlled the modern northern Jiangxi and eastern Hubei region, to submit to him. Emperor Gaozu sent his generals Li Xiaogong the Prince of Zhao Commandery, Li Jing, Huang Junhan, and Li Shiji against Fu, with Li Xiaogong in overall command. In winter 623, Zhang was captured by the Tang general Li Daliang, cutting off a flank support for Fu.
Defeat and death
For several months, Tang and Song forces battled on the border, but as the main forces under Li Xiaogong and Li Jing approached, Fu had his generals Feng Huiliang and Chen Dangshi take up defense positions at Mount Bowang, preparing for the assault. Fu's orders to Feng and Chen were to refuse engagement and to wear the Tang forces out, but Li Xiaogong cut off their food supplies, and so they abandoned the strategy and challenged Li Xiaogong. Most of Li Xiaogong's subordinates believed that Feng and Chen had a strong army and could not be easily defeated, and so that Li Xiaogong should bypass them and attack Danyang directly. However, Li Jing opposed, pointing out that if Tang forces did not defeat Feng and Chen first, they would not be able to siege the well-fortified Danyang easily. Li Xiaogong agreed and engaged Feng and Chen directly, defeating them, as the Song forces lost morale when they saw that Kan was fighting on the Tang side. Feng and Chen fled back to Danyang.Li Xiaogong and Li Jing trailed them and approached Danyang. Fu, in fear, abandoned Danyang and fled east, heading toward Kuaiji, a fortified city on Hangzhou Bay then defended by Zuo. On the way, however, his army began to desert, and he only had 500 men left when he reached Chang Prefecture. There, his subordinate Wu Sao considered seizing him and surrendering. When Fu discovered this, he fled with less than 100 guards; when he reached Wukang, he was attacked by the men of the country. After his confidant, Ximen Junyi, was killed in the battle, he was captured. He was delivered to Danyang, where Li Xiaogong executed him.