In Babylonian mythologyAnd doubtless in Sumerian mythology as well, though all the surviving texts are later. , Tiamat is a goddess who personifies the sea. Tiamat is considered the monstrous embodiment of primordial chaos.Stephanie Dalley, Myths from Mesopotamia (Oxford University Press, 1987), p. 329. Although there are no early precedents for it, some sources identify her with images of a sea serpent or dragon.such as Thorkild Jacobsen in "The Battle between Marduk and Tiamat", Journal of the American Oriental Society, 88.1 (January-March 1968), pp 104-108. In the Enûma Elish, the Babylonian epic of creation, she gives birth to the first generation of deities; she later makes war upon them and is killed by the storm-god Marduk. The heavens and the earth are formed from her divided body.Tiamat was known as Thalattē (as variant of thalassa, the Greek word for "sea") in the Hellenistic Babylonian Berossus' first volume of universal history. It is thought that the name of Tiamat
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http://en.wikipedia.org/wiki/Tiamat