Wu Sangui

In 1632, the Ming court transferred the Liaodong army to Shandong, to defeat the rebel armies of Kong Youde. Wu, who was 22 years old at that time, served as a guerrilla general and fought side by side with his father, Wu Xiang. Wu rose to the rank of deputy general and was promoted to full general in September of that year. In September 1638, Wu served as a deputy general again.[1]

At the beginning of 1639, as the situation in Liaodong became increasingly tense, the Ming court transferred general Hong Chengchou as the governor-general (Chinese: 总督; pinyin: Zǒngdū) of Jiliao; Hong appointed Wu as the general in charge of training.[1]

In October 1639, a Qing army of more than 10,000 men, commanded by Duoduo and Haoge, invaded Ningyuan. Jin Guofeng, full general of Ningyuan, immediately led troops to confront the Qing army but was surrounded and killed. Wu took Jin's place as full general of Ningyuan, and became a guardian general of Liaodong.[1]

After Wu served as the full general in Ningyuan, he made the local army the strongest in Liaodong, having 20,000 troops at Ningyuan town. To enhance their combat power, Wu selected 1,000 elite soldiers to form a fearless battalion. The battalion was trained and commanded by Wu himself, making these men his bodyguard who would come at Wu's call at any time. They were the core of his army and laid the foundation for Wu's military achievements.[1]

In March 1640, Hong Taiji appointed Jirgalang and Duoduo as left and right commander, respectively, marching towards the north of Jinzhou. Aiming to besiege Jinzhou, they reestablished Yizhou, garrisoned the troops, opened up wasteland, grew food grain, and forbade any cultivation in the Ningjin area outside Shanhai Pass.[1]

On 18 May 1640, Wu Sangui met the Qing army in battle at Xingshan. Jirgalang led 1,500 soldiers to accept the surrender of the Mongolian people, but they were spotted by general Liu Zhaoji when passing the Ming army. Liu Zhaoji led 3,000 soldiers against the Qing army. At that time, Wu Sangui was stationed in Songshan and brought a 3,000-strong force the moment he heard the news. From Jinzhou, Zu Dashou sent more than 700 soldiers as a reserve. At first, the Ming army seemed more powerful with superior numbers; but, after the pursuit of Jiamashan, the Qing army was able to surround Wu Sangui.[1]

Wu Sangui was unable to withstand the repeated attacks from both Jirgalang and Duoduo. He fought a bloody battle with the Qing army, but could not break through the siege until Liu Zhaoji came to his rescue. The Ming army casualties were more than 1000, with deputy general Yanglun and Zhou Yanzhou dead, but Wu Sangui's bravery was still praised.[1]

On 25 April 1641, the battle of Songjin began with an attack by the Ming army, Wu Sangui leading and personally killing ten enemies, defeating the Qing cavalry. After the battle, Wu Sangui was regarded as its most outstanding general.[2]

Wu Sangui (center)

In June 1641, Hong Chengchou and Wu Sangui returned to Songshan and garrisoned the northwest area. Prince Zheng Jirgalang attacked several times towards Songshan and Xinshan but was defeated repeatedly, the Ming army succeeding in surrounding the Qing army four times. Though the Qing army finally broke through the encirclement, their casualties were very high. Due to Wu Sangui's bravery, the Ming army remained on the offensive, but it also paid a heavy price.[2]

On 20 August 1641, the Ming army attacked the Qing camp. The battle lasted the whole day, and the result was too close to call. However, Prince Ajige unexpectedly captured the Ming army's provisions in Bijia Mountain, significantly undermining their ability to fight. The battle continued on 21 August, and was unfavourable to the Ming army.[2] After this defeat Datong full general Wang Pu lost the will to fight. Before Hong Chengchou issued orders, Wang fled with his troops, which completely disrupted the original breakthrough plan. More surprisingly, Wu Sangui also fled in the chaos, escaping on Wang's heel. At such a life-or-death moment, Wu revealed selfishness.[2]

The Ming army attempted to withdraw, pursued by the Qing. In a matter of a few days, more than 53,000 people and 7,400 horses of the Ming army were killed. They had no way to flee and no will to fight. Only 30,000 survived after fleeing back to Ningyuan.[2]

Wu Sangui survived not only by following Wang Pu, but by having a good retreat plan. When Hong Chengchou ordered the breakthrough, Wu Sangui went back to his camp and immediately discussed tactics with his generals. They decided to give up the small path and flee on the main road. As expected, the Qing army had only cut off the small path, while no more than 400 soldiers held the main road under Hong Taiji. Seeing Wu Sangui's fierce charge, Hong Taiji restrained his army from pursuing. Hong thought highly of Wu, and considered gaining his favor as the key to conquering the dynasty.[2]

The breakthrough at Songshan resulted in the deaths of 52,000 members of the Ming elite army, which greatly wounded the Ming dynasty. Wu and Wang Pu could not escape the fate of being punished for fleeing and avoiding combat and were sentenced to death.[2]

A few days later, Wu, who had fled to Ningyuan, received the imperial decree of the Chongzhen emperor. Surprisingly, Wu was promoted above all the full generals. This implied that Wu would not be punished, which was beyond the comprehension of many government officials. Even more surprising was the fact that, months later, when someone in the court called for an investigation to determine responsibility for the Songshan defeat, only Wang Pu was arrested while Wu continued to serve as a governor general of Liaodong, garrisoned in Ningyuan. This caused an outcry in the Ming court.[2]

In May 1642, the result of the Ming court's re-examination was the death penalty for Wang Pu, and demotion of three levels in rank for Wu. Wu continued to serve as full general in Ningyuan and was in charge of the training of the Liaodong army.[2]

By February 1642, the Ming Dynasty had lost four of the eight vital cities beyond the Shanhaiguan Pass to the Manchu army. Ningyuan, where Wu was stationed, became Beijing's last defence against the Manchu army. Hong Taiji repeatedly attempted to persuade Wu to surrender, to no avail.[3] Wu did not side with the Qing Dynasty until after the defensive capability of the Ming Dynasty had been greatly weakened with its political apparatus destroyed by the rebel armies of Li Zicheng's Shun dynasty.

In early 1644, Li Zicheng, the head of a peasant rebel army, launched his force from Xi'an for his final offensive northeast toward Beijing. The Chongzhen Emperor decided to abandon Ningyuan and called upon Wu to defend Beijing against the rebels. Wu Sangui received the title Pingxi Bo (Chinese: 平西伯; pinyin: Píng xībó; lit. 'Count who pacifies the West') as he moved to face the peasant army.[4]

At the time of Beijing's fall to Li Zicheng, on 25 April 1644, Wu and his 40,000-man army—the most significant Ming fighting force in northern China—were on the way to Beijing to come to the Chongzhen Emperor's aid but then received word of the emperor's suicide. So they garrisoned the Shanhai Pass, the eastern terminus of the main Great Wall instead. Wu and his men were then caught between the rebels within the Great Wall and the Manchus without.[5]

After the collapse of the Ming dynasty, Wu and his army became a vital military force in deciding the fate of China. Both Dorgon and Li Zicheng tried to gain Wu's support.[6] Li Zicheng took a number of measures to secure Wu's surrender, granting silver, gold, a dukedom, and most crucially by capturing Wu's father Wu Xiang, ordering the latter to write a letter to persuade Wu to pledge allegiance to Li.[3][6]

Battle of Shanhai Pass in which Wu Sangui surrendered to Qing dynasty

At first, Wu intended to surrender to Li Zicheng, but when he heard of the predatory behaviour of Li's army and his father's captivity, he changed his plans.[3] Instead, he killed Li's envoy. To save the life of his family, he wrote back to his father scolding him for his disloyalty and claiming to be breaking relations with his father. Furthermore, he sent several generals to pretend to pledge allegiance to Li.[7] He knew that his force alone was insufficient to fight Li's main army.[8] He wrote to Dorgon for military support, under the condition of restricting the dominance of Ming and Manchus to southern and northern China, respectively, claiming to resume the Ming Dynasty. The Manchu prince-regent Dorgon determined that this was an opportunity to claim the Mandate of Heaven for the Qing.[9] Dorgon made clear in his reply that the Manchus would help Wu, but Wu would have to submit to the Qing. Wu did not accept at first.[3]

Li Zicheng sent two armies to attack the pass, but Wu's battle-hardened troops defeated them easily on 5 and 10 May 1644.[10] In order to secure his position, Li was determined to destroy Wu's army. On 18 May, he personally led 60,000 troops out of Beijing to attack Wu.[10] and defeated Wu on 21 May. The next day, Wu wrote to Dorgon for help. Dorgon took the opportunity to force Wu to surrender,[7] and Wu had little choice but to accept.[11] On 22 May 1644, Wu opened the gates of the Great Wall of China at Shanhai Pass to let Qing forces into China proper, forming an alliance with the Manchus.[12] Wu ordered his soldiers to wear white cloths attached to their armour, to distinguish them from Li Zicheng's forces.[13] Together, Wu's army and the Qing forces defeated the Shun rebels in the Battle of Shanhai Pass on 27 May 1644. Having defeated Li's main army, the Qing marched into Beijing unopposed and enthroned the young Shunzhi Emperor in the Forbidden City.[14] Wu pledged allegiance to the Qing dynasty.[3]

Qing seal for Wu as General Who Pacifies the West

Wu Sangui surrendered to the Qing dynasty and received the title of Pingxi Wang (Chinese: 平西王; pinyin: Píngxī wáng; lit. 'Prince who pacifies the West'). However, he remained fearful that the Qing dynasty held him in suspicion.[2]

In October 1644, Wu received orders to suppress the rebel peasant army. At that time, Li Zicheng still held Shanxi, Hubei, Henan, and other areas, and was gathering his troops to rise again. Wu, together with Shang Kexi, led his soldiers to Shanxi against the rebel army under Ajige, the General of Jingyuan appointed by the prince regent Dorgon. From October to the following August, when he returned to Beijing, Wu fought the peasant army and achieved great success.[2]

Li Zicheng held a grudge against Wu for his faithlessness, so he executed thirty-eight members of the Wu household, including Wu's father, whose head was displayed on the city wall. Enraged, Wu hardened his resolve to resist the new regime and defeated the Shun vanguard led by Tang Tong on 3 and 10 May.[15] In June 1645, Wu Sangui captured Yulin and Yan'an. At the same time Li Zicheng was killed by a village head in Tongshan county, Hubei Province.[3]

In 1645, the Qing court rewarded Wu Sangui with the title of Qin Wang (Chinese: 亲王; pinyin: Qīnwáng; lit. 'Prince of the Blood') and ordered him to garrison Jinzhou. The high-sounding title was belied by transferring Wu to Jinzhou, which had lost its position as a militarily important town and become an insignificant rear area. Moreover, along with a large number of Manchu and Han people migrating into central China, it had become sparsely populated and desolate. Hence, Wu felt perplexed and upset.[2]

On 19 August 1645, before Wu returned to Liaodong from Beijing, he submitted his request to the Qing imperial court to renounce his title as Qin Wang (Prince). After giving up his title, he began to make efforts to consolidate his strength by demanding troops, territory, compensation, and reward for the generals under his command, which were all granted by the imperial court.[2]

In July 1646, when Wu Sangui was summoned by the emperor, the Qing court granted him a total of 10 horses and 20,000 pieces of silver as an extra reward. Wu wasn't pleased, however, since he had been set aside since his return to Jinzhou, while the army of Kong Youde, Geng Jingzhong, and Shang Kexi had been fighting against the South Ming Dynasty in Hunan and Guangxi since 1646.[2]

In 1648, the rebellion against the Qing dynasty reached its climax. In the west, Jiang Xiang, the full general of Datong, waged an insurgency in Shanxi, while, in the south, in Nanchang and Guangzhou, Jin Shenghuan and Li Chengdong also rebelled, which dramatically changed the military situation.[2]

The rebellion from the surrendered Han generals greatly shocked the Qing dynasty rulers. They came to realize the significance role of these conquered generals to the control of central China, as well as the importance of the strategy of "using Han to rule Han" (以汉制汉). In this situation, Wu thrived again.[2]

At the beginning of 1648, the Qing imperial court ordered Wu to move his family west and garrison Hanzhong as Pingxi Wang with Chief General (Du Tong) of the Eight Banners Moergen and Li Weihan. In less than one year, Wu suppressed the rebellion in most regions of Shanxi and reversed the situation in the northwest. After that, Wu, charging at the head of his troops in every battle, proved his loyalty to the Qing dynasty. After four years of struggle, peace came to Shaanxi province. Wu was praised for his contribution by the Qing imperial court, and his status rose.[6]

In 1652, the rebel Daxi army became the main force rebelling against the Qing. The situation was made difficult by the deaths of the Qing generals Kong Youde and Ni Kan, when the rebels Li Dingguo and Liu Wenxiu's troop marched into Sichuan. The Qing imperial court then summoned Wu to suppress the Daxi army in Sichuan. However, Wu Sangui was being closely watched by general Li Guohan, a trusted advisor to the imperial court. Wu wasn't able to free himself from surveillance until a few years later, when Li Guohan died. Hence, Wu enhanced his military strength rapidly by gaining a large number of enemy surrenders.[6]

In 1660, the Qing army split into three parts, marched into Yunnan province, and eliminated the South Ming Dynasty, thus achieving the preliminary unification of the mainland. Nevertheless, the imperial court still faced a number of serious military and political threats. The Yongli Emperor of the Southern Ming dynasty and Li Dingguo of the Daxi army retreated to Burma, and they maintained influence in Yunnan. It was inconvenient for the Eight Banners soldiers to garrison the Yunnan Guizhou border area, which was far away from the capital. As a result, the imperial court could only approve the proposal by Hong Chengchou to withdraw those soldiers, and give Wu, and his army, command of the border area. Thus, Wu not only commanded a large army but also controlled vast territory.[6]

In 1661, the green-flag army under Wu numbered 60,000, while Shang Kexi and Geng Jimao had only 7,500 ad 7,000 soldiers in their armies. Wu planned to permanently garrison and was preparing to make the border area his own. However, Yunnan was not stable at that time, for newly surrendered soldiers had not been fully assimilated into the Qing force. Moreover, the Daxi army had been building in Yunnan over decades and shared a close relationship with various minority nationalities. Many Tusi leaders refused to accept the rule of Wu, which led to a series of rebellions. The existence of the Yongli Emperor of the Southern Ming dynasty and Li Dingguo's army was regarded as a great threat to Wu. Therefore, Wu was actively preparing for their elimination to consolidate his rule. He exaggerated the rebellion's threat, spread rumors. and submitted his proposal to the court, urging the invasion of Burma, which, after a time, the imperial court approved.[6]

In June 1662, the Yongli Emperor was captured and killed, while Li Dingguo died of illness.[6] In the next few years, Wu led his army from the northwest to the southwest border and enabled the Qing dynasty's dominance in that part of the country.