There is a saying in the "Round Round Song": "Weeping for the six armies, Chong Guan is angry and red." "Folk legend says that the reason why Wu Sangui descended to Qing was only to regain the love in his heart - Chen Yuanyuan, if such a passionate man is put into modern times, I am afraid that he has already become a model of a good man." However, history is always cruel, in that era, no one would do such a great rebellion for a woman, not to mention that Wu Sangui was the king of Pingxi, as the last straw to save the Ming Dynasty, he would never be so hasty.
In 1643, Wu Sangui wrote a letter to Emperor Taiji, although he did not explicitly express his intention to surrender, but his act of sending letters had explained everything, and both of them tacitly agreed to this. Soon after, the Qing army launched an offensive, and as the cities fell one by one, Wu Sangui's Ningyuan also became an isolated city outside Shanhaiguan. For the Qing army, Wu Sangui was no longer important, and even if he refused to surrender, he could not change the fate of the fall of the Ming Dynasty.
In March 1644, the Chongzhen Emperor crowned Wu Sangui as Pingxi Bo, and in the face of the Qing army's pressing, he asked Wu Sangui to immediately lead the army into Beijing. Unfortunately, Wu Sangui still took a slow step, and when he reached the halfway point, he heard the news of Chongzhen hanging himself, and for a moment, he was like a duckweed in the sea, with nowhere to go. However, Wu Sangui still had two choices, one was to surrender to Li Zicheng, the other was to surrender Torgon, and he could only choose one of the two to survive in the cracks.
Later, Wu Sangui's concubine Chen Yuanyuan was captured by Li Zicheng's subordinates, and his family also became Li Zicheng's hostages, and in desperation, he could only negotiate peace with Li Zicheng first, but behind his back, Wu Sangui asked Dorgon for help, and he was willing to use the power of the Qing army to destroy Li Zicheng on the condition of "dividing the north and the south". In this way, Li Zicheng, without any defense, led an army of 60,000 people straight to Shanhaiguan, and if all went well, he would soon fall into Wu Sangui's trap.
Unexpectedly, Wu Sangui's men exposed their horses' feet in advance, and Li Zicheng was extremely angry and immediately launched an attack on Wu Sangui. Due to the disparity in strength between the two sides, Wu Sangui had to urge Dolgun to send troops quickly, and once the fighter plane was missed, the previous efforts would be wasted. However, Dorgon took this opportunity to force Wu Sangui to surrender to the Qing Dynasty, and from then on, the two sides were no longer cooperative, but superior and inferior. In this way, in the Battle of Yishi, Li Zicheng was defeated by the combined forces of Wu Sangui and Dolgun, and the Qing army, which was unhindered, also successfully entered the pass and put the young Shunzhi on the throne.
Later, Wu Sangui was made the King of Pingxi and was responsible for guarding Yunnan, but at this time, although he was the first hero of the Manchu Qing Dynasty, at the same time, he was also a "traitor" in the eyes of the common people, and the emperor was always wary of him, worried that he would raise an army to rebel. Therefore, Wu Sangui rebelled in 1673, and in order to be justified, he also issued a military essay, but unfortunately, only one original version of this text remains, which is now in the "Huayi Perversion" written by the Japanese Edo shogunate Confucian officials Lin Shu and Lin Fengyin.
The text reads: The town is deeply nagged by the Ming Dynasty Lord, Tongzhen Shanhaiguan. For a while, Li rebelled against the chaos and gathered millions of people... Forced to make an alliance in blood, Xu Yu was sealed, temporarily borrowed 100,000 Yi soldiers, as a precursor, beheaded into the customs, Li Thief escaped... That is to say, Wu Sangui had no intention of surrendering to Qing, he just wanted to borrow the Qing army to avenge Chongzhen, and perhaps future generations would blame him. However, this is just the words of Wu Sangui's family, how much of it is true and how much is false?