The Tigris and Euphrates river basin did have massive floods from time to time. One notable in 3500 BC, another in 2900 BC caused by snowmelt from the Zagros mountains combined with spring rains. There's flood sediment and a King's list. The Flood: Mesopotamian Archaeological Evidence | National Center for Science EducationChina's great flood appeared around 2300 BC
( thanks for using BC before christ)
Great Flood (China) - Wikipedia
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