A people living in southern Mesopotamia in the 4th and 3rd millennia bc. By 3000 bc a number of city states had developed in Sumer, such as Uruk, Eridu, and Ur. The Sumerians are credited with inventing the cuneiform system of writing, which was originally pictographic but gradually became stylized. Many simple inscriptions survive as evidence of this development; they also attest the increase in administration that accompanied urban growth. Their literature contains references to myths, hymns, and incantations. They developed a legal system, supported by complex political and economic organization. Their technological achievements included wheeled vehicles and potters' wheels, as well as such architectural features as columns, vaults, and domes.
The first great empire of Sumer was established by the people of Akkad, who conquered the area in about 2350 under the leadership of Sargon. The dynasty founded by him was destroyed in about 2200, and after 2150 the kings of Ur not only re-established Sumerian sovereignty in Sumer but also conquered Akkad. This new empire lasted until roughly 2000 when pressure from the Elamites and Amorites reached its culmination with the capture and devastation of Ur. The Sumerians at this point disappear from history, but the influence of their culture on the subsequent civilizations of Mesopotamia was far-reaching.