Disaster of Yongjia

The Disaster of Yongjia (Chinese: 永嘉之祸) referred to events that occurred in 311 CE, when Wu Hu forces captured and sacked Luoyang, the Jin capital. After this victory, Wu Hu forces committed a massacre when entering the city, killing the Jin crown prince, a host of ministers, and over 30,000 civilians. They also burnt down the palaces and dug up Jin mausoleums. This was seen as the event that led to the fall of the unified Jin dynasty and its re-establishment as the Eastern Jin dynasty, as well as the loss of northern China to non-Chinese forces.
References

Book of Jin

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