The deadliest flood in human history occurred in China in 1931 when the Yangtze River overflowed its banks. An estimated 51 million people were affected, 3.7 million of whom died.
The rivers of China are among the most susceptible to flooding in the world, with as much as two thirds of the country's land area prone to flood disasters. Because so many people live along the Yangtze, massive floods along this river are particularly devastating. Several other flood events, such as those that occurred in 1911 and 1935, also carried death tolls in excess of 100,000.