Ningursu, Lord of Destruction

Thorkild Jacobsen explained the origins of one Sumerian god like this:

One must realize that Ningirsu was the yearly flood of the river Tigris personified. Each year when the winter snows begin to melt in the high mountains of Iran they pour down through the foothills in numerous mountain streams to swell the Tigris. This was experienced theologically as the deflowering of the virgin foothills, Nin-Hursag, by the great mountains, Kur-gal, farther back; the waters of the flood being his semen. Kur-gal, whose other name was Enlil, is thus Ningursu's father. Ningirsu's mother is Nin-Hursag, Lady Foothills, and the reddish brown colour of the flood waters which comes from the clay picked up by the water in passing through the foothills is seen as due to blood from her deflowering. The flood to which all this refers, the god Ningirsu himself, is awesome indeed. . . .