In 1644, Li Zicheng made the stupidest and most ruinous decision of his life to date.

On the retreat from Beijing after defeat in battle, he was furious and ordered the complete slaughter of Wu Sangui's entire family, including Wu Sangui's father Wu Xiang—thirty-four members of the Wu family, none spared, all killed.
It was this order that completely pushed Wu Sangui to the brink, and also personally buried the dynasty he had just seized.
Before this, Wu Sangui was actually still hesitating, watching the fall of the Ming Dynasty and weighing whether to surrender to the Shun. He still kept a way out in his heart, not fully giving up.
But after his entire family was exterminated, he had no more options left—only to fight to the death, surrender to the Qing, and seek revenge to the end.
His subordinates urged him not to act impulsively, but Wu Sangui ignored them all, directly ordering the army to prepare for battle and to ally with the Qing army.
Back in March 1644, Li Zicheng captured Beijing, Chongzhen hanged himself, and the Ming Dynasty was completely overthrown.
When he first entered the city, the situation was still relatively stable—people watched cautiously, officials surrendered, and it seemed that Shun was about to sit firmly on the throne.
Li Zicheng also issued decrees to reduce taxes and restore order, which initially gained public support.
However, the Shun army lacked governance ability and could not control their generals.
Military discipline quickly collapsed, chaos erupted everywhere.
General Liu Zongmin was busy embezzling and collecting funds, using harsh punishments on Ming officials, and plundering wealth everywhere.
Wu Sangui's father Wu Xiang was captured and tortured for money, his family property confiscated, and even Wu Sangui’s beloved concubine Chen Yuanyuan was forcibly taken.
Far at Shanhaiguan, Wu Sangui had already received Li Zicheng’s surrender invitation and a letter from his father urging surrender, and he was preparing to lead troops to submit in Beijing.
Halfway there, a series of bad news arrived: his father was beaten, his family property confiscated, his mistress stolen.
Wu Sangui initially couldn’t believe it; after confirming the news was true, he saw through Li Zicheng’s insincerity and immediately ordered a halt and turned back to Shanhaiguan.
Faced with a difficult homecoming and burning anger, Wu Sangui immediately contacted Dorgon, deciding to use the Qing troops to enter the pass.
In April, the Battle of Shanhai Pass broke out, with Wu Sangui and the Qing army joint forces attacking, and Li Zicheng was defeated and retreated.
During the retreat, Li Zicheng, humiliated and furious, publicly executed Wu Xiang in Yongping, hanging his head for display.
Back in Beijing, to vent his anger, he ruthlessly slaughtered all thirty-four members of the Wu family.
This act of revenge seemed satisfying but was actually self-destructive.
The people in Beijing were thrown into chaos—officials fled, civilians panicked, and military morale was completely shattered.
Li Zicheng hastily declared himself emperor in Wuying Hall, but he never sat firmly on the throne and quickly abandoned the city to escape.
The Qing army took advantage of the situation and took control of Beijing, stabilizing the situation.
Wu Sangui was resolute in becoming the Qing’s vanguard, pursuing the Shun army from North China to Shaanxi and Hubei.
In just one year, Li Zicheng’s Shun regime collapsed and was utterly defeated.
Li Zicheng’s defeat was not due to poor fighting or lack of troops, but because of a narrow vision and reckless impulsiveness.
He originally held a strong hand—controlling the capital, winning the people's hearts, and holding the world—yet due to poor management and excessive killing to vent anger, he turned potential allies into enemies and personally handed over the empire.
In times of chaos, the most dangerous mistake is to kill all rivals and leave no room for retreat.
Li Zicheng’s ruthless revenge ultimately led to the downfall of his dynasty.