According to Wikipedia:
“The Anunnaki (also transcribed as: Anunna, Anunnaku, Ananaki and other variations) are a group of deities in ancient Mesopotamian cultures (i.e. Sumerian, Akkadian, Assyrian, and Babylonian). The name is variously written “da-nuna”, “da-nuna-ke-ne”, or “da-nun-na”, meaning something to the effect of “those of royal blood” or “princely offspring”. According to The Oxford Companion to World Mythology, the Anunnaki “are the Sumerian deities of the old primordial line; they are chthonic deities of fertility, associated eventually with the underworld, where they became judges. They take their name from the old sky god An (Anu).”
Author Zecharia Sitchin popularized the notion of the Annunaki being responsible for the creation of Sumerian civilization, and proposed a possible explanation for human origins involving ancient astronauts. While Sitchin’s hypothesis has been disregarded by academics and scientists as “pseudoscience”, he firmly stands by his theory.
Whether the presence of the Annunaki is fact or fiction is still up for debate – however, the conceptual idea of their role in the evolution of humanity is interesting nonetheless.
To learn more about the Annunaki, the video below presents an interesting argument about who they are, and why they came here.