From The Art and Popular Culture Encyclopedia
The Sumerians practiced a polytheistic religion, with anthropomorphic gods or goddesses representing forces or presences in the world, in much the same way as later Greek mythology. According to said mythology, the gods originally created humans as servants for themselves but freed them when they became too much to handle.
Many stories in Sumerian religion appear similar to stories in other Middle-Eastern religions. For example, the Biblical account of the creation of man as well as Noah's flood resemble the Sumerian tales very closely. Gods and Goddesses from Sumer have distinctly similar representations in the religions of the Akkadians, Canaanites, and others.