The Kaifeng Flood

China, 1642. Death toll: 300, 000.

Although technically a natural disaster the Kaifeng Flood was actually a military effort. Kaifeng which is located in the Henan province was flooded by the Ming army with water from the Yellow River. This was done to prevent the rebel Li Zicheng taking over Kaifeng and halved the population from 600, 000 to around 300, 000 through the initial flooding and post flood famine.