Anu (in Akkadian; Sumerian: An, from ?An "sky, heaven") is the earliest attested Sky Father deity. In Sumerian religion, he was additionally "King of the Gods", "Lord of the Constellations, Spirits and Demons", and "Supreme Ruler of the Kingdom of Heaven", where Anu himself wandered the highest Heavenly Regions. He was believed to have the power to judge those who had committed crimes, and to have created the stars as soldiers to destroy the wicked. His attribute was the Royal Tiara. His attendant and vizier was the god Ilabrat.
In Sumerian, the designation "An" was used interchangeably with "the heavens" so that in a few cases it is doubtful whether, under the term, the god An or the heavens is being denoted. The Akkadians inherited An as the god of heavens from the Sumerian as Anu-, and in Akkadian cuneiform, the DINGIR character might refer either to Anum or to the Akkadian word for god, ilu-, and consequently had two phonetic values an and il. Hittite cuneiform as adapted from the Old Assyrian kept the an value but abandoned il.
Divine genealogy and syncretisms
The earliest texts make no reference to An's origins. Later he's regarded as the son of Anšar and Kišar, as in the first millennium creation epic Enūma eliš [aka THE ENUMA ELISH](Tablet I, 11-14). In Sumerian texts of the third millennium the goddess Uraš is his consort; later this position was taken by Ki, the personification of earth, and in Akkadian texts by Antu, whose name is probably derived from his own.
An/Anu frequently receives the epithet "father of the gods," and a large number of deities are described as his children in one context or another. Inscriptions from third-millennium Lagaš name An as the father of Gatumdug, Baba and Ningirsu. In later literary texts, Adad, Enki/Ea, Enlil, Girra, Nanna/Sin, Nergal and Šara additionally appear as his sons, while goddesses referred to as his daughters include Inana/Ištar, Nanaya, Nidaba, Ninisinna, Ninkarrak, Ninmug, Ninnibru, Ninsumun, Nungal and Nusku. An/Anu is additionally the head of the Annunaki, and created the demons Lamaštu, Asag and the Sebettu. In the epic Erra and Išum, Anu gives the Sebettu to Erra as weapons with which to massacre humans when their noise becomes irritating to him (Tablet I, 38ff).
When Enlil rose to equal or surpass An in authority, the functions of the two deities came to a few extent to overlap. An was additionally at times equated with Amurru, and, in Seleucid Uruk, with Enmešara and Dumuzi.
The doctrine once established remained an inherent part of the Babylonian-Assyrian religion and led to the more or less complete disassociation of the three gods constituting the triad from their original local limitations. An intermediate step between Anu viewed as the local deity of Uruk, Enlil as the god of Nippur, and Ea as the god of Eridu is represented by the prominence which each one of the centres associated with the three deities in question must have acquired, and which led to each one absorbing the qualities of additional gods so as to give them a controlling position in an organised pantheon. For Nippur we have the direct evidence that its chief deity, En-lil, was once regarded as the head of the Sumerian pantheon. The sanctity and, therefore, the importance of Eridu remained a fixed tradition in the minds of the people to the latest days, and analogy therefore justifies the conclusion that Anu was likewise worshipped in a centre which had acquired great prominence.
The summing-up of divine powers manifested in the universe in a threefold division represents an outcome of speculation in the schools attached to the temples of Babylonia, but the selection of Anu, Enlil (and later Marduk), and Ea for the three representatives of the three spheres recognized, is due to the importance which, for one reason or the other, the centres in which Anu, Enlil, and Ea were worshipped had acquired in the popular mind. Each of the three must have been regarded in his centre as the most important member in a larger or smaller group, so that their union in a triad marks additionally the combination of the three distinctive pantheons into a harmonious whole.
In the astral theology of Babylonia and Assyria, Anu, Enlil, and Ea became the three zones of the ecliptic, the northern, middle and southern zone respectively. The purely theoretical character of Anu is thus still further emphasized, and in the annals and votive inscriptions as well as in the incantations and hymns, he's rarely introduced as an active force to whom a personal appeal can be made. His name becomes little more than a synonym for the heavens in general and even his title as king or father of the gods has little of the personal element in it. A consort Antum (or as a few scholars prefer to read, Anatum) is assigned to him, on the theory that every deity must have a female associate. But Anu spent so much time on the ground protecting the Sumerians he left her in Heaven and then met Innin, whom he renamed Innan, or, "Queen of Heaven". She was later known as Ishtar. Anu resided in her temple the most, and rarely went back up to Heaven. He is additionally included in the Epic of Gilgamesh, and is a major character in the clay tablets.
born to Namma
born to Namma
born to Uraš
maybe daughter of Enlil
maybe son of Enki
maybe born to Ninḫursaḡ
born to Uraš
maybe daughter of Enki
maybe son of Enki