Fragments Of Chaldean History, Berossus: From Alexander Polyhistor:

"Berossus, in the first book of his history of Babylonia, informs us that he lived in the age of Alexander the son of Philip. And he mentions that there were written accounts, preserved at Babylon with the greatest care, comprehending a period of above fifteen myriads of years: and that these writings contained histories of the heaven and of the sea; of the birth of mankind; and of the kings, and of the memorable actions which they had achieved.

He wrote of Omoroca:

"There was a time in which there existed nothing but darkness and an abyss of waters, wherein resided most hideous beings, which were produced of a two-fold principle. There appeared men, some of whom were furnished with two wings, others with four, and with two faces. They had one body but two heads: the one that of a man, the other of a woman: and likewise in their several organs both male and female.

Other human figures were to be seen with the legs and horns of goats: some had horses' feet: while others united the hind quarters of a horse with the body of a man, resembling in shape the hippocentaurs. Bulls likewise were bred there with the heads of men; and dogs with fourfold bodies, terminated in their extremities with the tails of fishes: horses also with the heads of dogs: men too and other animals, with the heads and bodies of horses and the tails of fishes.

In short, there were creatures in which were combined the limbs of every species of animals. In addition to these, fishes, reptiles, serpents, with other monstrous animals, which assumed each other's shape and countenance. Of all which were preserved delineations in the temple of Belus at Babylon.

The person, who presided over them, was a woman named Omoroca; which in the Chaldæan language is Thalatth; in Greek Thalassa, the sea; but which might equally be interpreted the Moon. All things being in this situation, Belus came, and cut the woman asunder: and of one half of her he formed the earth, and of the other half the heavens; and at the same time destroyed the animals within her."

All this (he says) was an allegorical description of nature. For, the whole universe consisting of moisture, and animals being continually generated therein, the deity above-mentioned took off his own head: upon which the other gods mixed the blood, as it gushed out, with the earth; and from thence were formed men. On this account it is that they are rational, and partake of divine knowledge."

In Babylonian myths, Tiamat (linked to Omoroca) 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 BCE, 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.

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