<P> Modern historians have suggested that Sumer was first permanently settled between c. 5500 and 4000 BC by a West Asian people who spoke the Sumerian language ( pointing to the names of cities , rivers , basic occupations , etc. , as evidence ) , an agglutinative language isolate . These conjectured , prehistoric people are now called `` proto - Euphrateans '' or `` Ubaidians '' , and are theorized to have evolved from the Samarra culture of northern Mesopotamia . The Ubaidians ( though never mentioned by the Sumerians themselves ) are assumed by modern - day scholars to have been the first civilizing force in Sumer , draining the marshes for agriculture , developing trade , and establishing industries , including weaving , leatherwork , metalwork , masonry , and pottery . </P>
<P> Modern historians have suggested that Sumer was first permanently settled between c. 5500 and 4000 BC by a West Asian people who spoke the Sumerian language ( pointing to the names of cities , rivers , basic occupations , etc. , as evidence ) , an agglutinative language isolate . These conjectured , prehistoric people are now called `` proto - Euphrateans '' or `` Ubaidians '' , and are theorized to have evolved from the Samarra culture of northern Mesopotamia . The Ubaidians ( though never mentioned by the Sumerians themselves ) are assumed by modern - day scholars to have been the first civilizing force in Sumer , draining the marshes for agriculture , developing trade , and establishing industries , including weaving , leatherwork , metalwork , masonry , and pottery . </P>
when did the sumerians emerge as a civilization
when did the sumerians emerge as a civilization
c. 5500 and 4000 BC
c. 5500 and 4000 BC