Noah's God behaves similarly to the Mesopotamian Gods depicted in The Epic of Gilgamesh. In particular, Noah's God may have been considered either identical to or closely related to the Mesopotamian God Ea.
Ea is a supreme creator deity central to ancient Mesopotamian ritual and cosmology. The Epic of Gilgamesh depicts several stories concerning Ea. In one story, Ea -- displeased with mankind's immorality and lack of piety -- orders the gods to downpour a destructive flood on humanity. The flood must destroy all of mankind along with all animal and plant life; it must leave nothing but soaked wasteland in its wake.
However, Ea becomes convinced to spare one single upright family. He delivers a message of the oncoming flood into the dream of one pious elder, along with instructions for building an ark. The story contains several parallels to the story of Noah's Ark, including such details as the sending out of a bird to check for dry land, and the landing of the ark atop mountain. These striking similarities suggest that the stories of both Gilgamesh and Noah's Ark may refer to the same deity.