The ancient Sumero-Babylonian god of the firmament, the 'great above', and the son of the first pair of gods, Ansar and Kisar, descendant of Apsu and Tiamat. He is referred to as "the Father" and "King of the Gods", which signifies his importance in the Mesopotamian pantheon. Not only is he the father of the gods, but also of a great number of demons, whom he sends to humans. In the Sumerian cosmology there was, first of all, the primeval sea, from which was born the cosmic mountain consisting of heaven, 'An', and earth, 'Ki'. They were separated by Enlil, then Anu carried off the heavens, and Enlil the earth. Anu later retreated more and more into the background. He retires to the upper heavens and leaves the affairs of the universe to Marduk and a younger generation of gods.