Scholars use the term "Igigi" to refer to the mythological Sumerian deities. In their opinion, the Igigi were the junior servants of the Anunnaki.
 
The myth of Atrahas—the Babylonian flood story and forerunner of the Gilgamesh flood story—describes the Sumerian paradise as a garden where the lower gods (Igigi) were forced to dig a watercourse for their masters, the Anunnaki.

The Igigi were constantly in orbit of our planet on giant platforms that processed ore delivered from Earth. After processing the minerals, the material was transferred to other ships and delivered to the Anunnaki home planet of Nibiru. Moreover, the Igigi were “too high for humanity” and “were not connected with people.”
 
After years of hard work, the Igigi rebelled. They "set fire to their tools and surrounded the Great House of Enlil by night", forcing the ancient Anunnaki to find another source of labor. The Igigi were eventually defeated and replaced by a more docile race, the humans.