These people called themselves the gag-gigga, meaning "black-headed people."  During the rule of Ennantum of Lagash, who unified many city-states and even extended the realm to Elam.  The last king of the Lagash dynasty, Lugal-Zage-Si was the last king of the ethnicity, conquering (*) Uruk, where he established his capital.  Following his rule, the lands came under the domination of Semitics from Akkad, during which their native language phased out of common ussage.  FTP
These people called themselves the gag-gigga, meaning "black-headed people."  During the rule of Ennantum of Lagash, who unified many city-states and even extended the realm to Elam.  The last king of the Lagash dynasty, Lugal-Zage-Si was the last king of the ethnicity, conquering (*) Uruk, where he established his capital.  Following his rule, the lands came under the domination of Semitics from Akkad, during which their native language phased out of common ussage.  FTP – What civilization is credited with the invention of the wheel, and the establishment of the first writing system, which is called cuneiform. 
These people called themselves the gag-gigga, meaning "black-headed people."  
{Sumerians} 