Sumerian (𒅴𒂠 EME.ĜIR₁₅ "native tongue") is the language of ancient Sumer, which was spoken in southern Mesopotamia (modern Iraq) since at least the 4th millennium BC. During the 3rd millennium BC, there developed a very intimate cultural symbiosis between the Sumerians and the Akkadians, which included widespread bilingualism. The influence of Sumerian on Akkadian (and vice versa) is evident in all areas, from lexical borrowing on a massive scale, to syntactic, morphological, and phonological convergence. This has prompted scholars to refer to Sumerian and Akkadian in the third millennium as a Sprachbund.

Akkadian gradually replaced Sumerian as a spoken language somewhere around the turn of the 3rd and the 2nd millennium BC (the exact dating being a matter of debate), but Sumerian continued to be used as a sacred, ceremonial, literary and scientific language in Mesopotamia until the 1st century AD. Then, it was forgotten until the 19th century, when Assyriologists began deciphering the cuneiform inscriptions and excavated tablets left by these speakers. Sumerian is a language isolate.

Zecharia Sitchin (July 11, 1920 – October 9, 2010) was an Azerbaijani-born American author of books proposing an explanation for human origins involving ancient astronauts. Sitchin attributes the creation of the ancient Sumerian culture to the Anunnaki, which he states was a race of extra-terrestrials from a planet beyond Neptune called Nibiru. He believed this hypothetical planet of Nibiru to be in an elongated, elliptical orbit in the Earth's own Solar System, asserting that Sumerian mythology reflects this view. Sitchin's books have sold millions of copies worldwide and have been translated into more than 25 languages.

Sitchin's ideas were rejected by scientists and academics, who dismiss his work as pseudoscience and pseudohistory. Sitchin's work has been criticized for flawed methodology and mistranslations of ancient texts as well as for incorrect astronomical and scientific claims.

Sitchin was born in the then Azerbaijan SSR of the Soviet Union, but was raised in Palestine. He received a degree in economics from the University of London, and was an editor and journalist in Israel, before moving to New York in 1952. While working as an executive for a shipping company, he taught himself Sumerian cuneiform and visited several archaeological sites.