The Sumerian civilization existed from 4100 B.C.E

The Sumerian civilization existed from 4100 B.C.E. until around 1750 B.C.E. The name "Sumer" meant "land of the civilized kings." The Sumerians were one of the first groups to divide time into hours and minutes. They also had a complex religion that involved gods called the Anunnaki. 

The Anunnaki were believed to be in charge of Sumerians’ fates. Many myths involved members of the Anunnaki passing judgment on humans. Additionally, the gods were described as children of the Earth and sky. Most people chalk these stories up to mythology, the same way they do the Greek gods. However, others wonder whether there’s more to the story