Mesopotamian religion was polytheistic(belief in or worship of multiple gods or deities), with followers worshipping several main gods and thousands of minor gods. The three main gods were Ea (Sumerian: Enki), the god of wisdom and magic, Anu (Sumerian: An), the sky god, and Enlil (Ellil), the god of earth, storms and agriculture and the controller of fates. Ea is the creator and protector of humanity in both the Epic of Gilgamesh and the story of the Great Flood.
In the latter story, Ea made humans out of clay, but the God Enlil sought to destroy humanity by creating a flood. Ea had the humans build an ark and mankind was spared. If this story sounds familiar, it should; foundational Mesopotamian religious stories about the Garden of Eden, the Great Flood, and the Creation of the Tower of Babel found their way into the Bible, and the Mesopotamian religion influenced both Christianity and Islam.
Each Mesopotamian City had its own patron god or goddess, and most of what we know of them has been passed down through clay tablets describing Mesopotamian religious beliefs and practices. A painted terracotta plaque from 1775 B.C. gives an example of the sophistication of Babylonian art, portraying either the goddess Ishtar or her sister Ereshkigal, accompanied by night creatures.