In Babylonian myths, Tiamat is a huge, bloated female dragon that personifies the saltwater ocean, the water of Chaos. She is also the primordial mother of all that exists, including the gods themselves. Her consort is Apsu, the personification of the freshwater abyss that lies beneath the Earth. From their union, saltwater with freshwater, the first pair of gods were born. They are Lachmu and Lachamu, parents of Ansar and Kisar, grandparents of Anu and Ea.
In the creation epic Enuma elish, written around 2000 BC, their descendants started to irritate Tiamat and Apsu so they decided to kill their offspring. Ea discovered their plans and he managed to kill Apsu while the latter was asleep. Tiamat flew into a rage when she learned about Apsu's death and wanted to avenge her husband. She created an army of monstrous creatures, which was to be led by her new consort Kingu, who is also her son. Eventually, Tiamat was defeated by the young god Marduk, who was born in the deep freshwater sea.
Marduk cleaved her body in half, and from the upper half he created the sky and from the lower half he made the earth. From her water came forth the clouds and her tears became the source of the Tigris and the Euphratus. Kingu also perished, and from his blood Marduk created the first humans.