Uruk period
The Uruk period (c. 4000 to 3100 BC) existed from the protohistoric Chalcolithic to the Early Bronze Age period in the history of Mesopotamia, following the Ubaid period. Named after the Sumerian city of Uruk, this period saw the emergence of urban life in Mesopotamia. It was followed by the Sumerian civilization. The late Uruk period (34–32 centuries) saw the gradual emergence of the cuneiform script and corresponds to the Early Bronze Age.