The rise of ancient Mesopotamian civilization occurred at the end of the fourth millenium in southern Mesopotamia alongside the Tigris and Euphrates rivers, where the Sumerians created city states, each with its local god. In Uruk there were two main temples: one was for Anu, the god of heaven; the other was for Inanna, the mother goddess of fertility, love and war. In addition, other deities were worshipped at other places – Enlil, lord of athmosphere at Nippur; Utu, the sun god, at Larsa; Nanna, the moon god, at Ur.
Each of these gods had a family and servants who were also worshipped ad various shrines. The temple itslef was located on a high platform and house in a holy room in which a statue of the god was washed, dressed and fed each day.
Through the centuries, Sumerian priests recounted stories about these gods, whose actions were restricted to various spheres of influence. In addition, the Sumerian myths contain legends about creation: Enlil, for example, separated heaven from earth, and Enki created man to grow food for himself and the gods.
During the next millenium, waves of Semitic people (known as the Akkadians) settled amongst the Sumerians, adopting their writing and culture. From 2300 BC, when Sargon of Akkad established the first Semitic empire, they dominated Mesopotamia. At this time Sumerian storiea were recorded in the Semitic language, Akkadian. These semites reshaped Sumerian culture, equating some of their gods with the Sumerian ones. Anu, for example, was identified with El; Inanna with Ishtar; Enki with Ea. In Akkadian schools epics of the gods were chronicled. The Gilgamesh epic, for example, depicts King Gilgamesh, who ruled Uruk in about 2700 BC.
For the Sumerians and the Akkadians, life was controlled by the gods. To obtain happiness, it was mandatory to keep the gods in a good humour through worship and sacrifice. None the less the gods were unpredictable, and this gave rise to the reading of omens. In the birth of monstrosities, the movements of animals, the shapes of cracks in the wall and the oil pured into water these peoples perceived the fingers of the gods pointing to the future. Thus if a person wished to marry, or a king chose to wage war, they would consult omens. Another frequent practice was to examine the liver of a sacrificed animal – a special class of priests was trained to interpret such signs. (From Dan Cohn-Sherbok, Atlas of Jewish History, Routledge 1994, p. 1)