Inanna is regarded as a daughter of the sky-god An. But she was also seen as the daughter of the moon-goddess Ningal and her consort Nanna. She is the sister of the underworld goddess Ereschkial and of the sungod Utu.

The Sumerian great "Lady Queen of Heaven" (Ninanna) who appears in two sources:  the Gilgamesh Epic, where she aids the hero and tries to seduce him, and in the Cycle of Inanna, a collection of poems concerning her relation - in life and death - to her brother and lover, the vegetation-god Dumuzi (akk. Tammuz).
Inanna figures prominently in various myths, such as 'Inanna's descent to the underworld'.
In this particular myth she travels to the realm of the dead and claims its ruling. However, her sister Ereshkigal, who rules the place, sentences her to death. With Inanna's death, however, nature died with her and nothing would grow anymore. Through the intervention of the god Enki she could be reborn if another person took her place. She choose her beloved consort Dumuzi, who would from then on rule the underworld every half year. This myth has some relations to the Demetermyth as well as to celtic believes. The vegetation dies and gets reborn. Tiamat was the ancient Sumero-Babylonian personification of the primordial salt waters of chaos. With her consort Apsu, the 'sweet' water, Tiamat mothered the first generation of the gods.

Tiamat took the form of a gigantic winged dragon, whose body was split in two by the hero marduk to create the heavens and the firmament: her upper body became the vault of heaven; the lower, the earth; her blood, the oceans.