Writing began as bookkeeping. In the temple economies of late fourth millennium Uruk, tokens and sealings for counting sheep and grain grew into signs pressed with a reed stylus into wet clay, and by about 3300 BCE the system could record language itself: cuneiform, wedge writing, the world's first script. With it came schools, contracts, letters, law and literature, and a scribal culture whose exercise tablets preserve the whole tradition.
Politically, Sumer was a quarrelsome family of city-states, united at intervals: by Sargon of Akkad, whose empire made Akkadian the language of rule around 2300 BCE and whose daughter Enheduanna served as high priestess of the moon at Ur; and by the Third Dynasty of Ur around 2100 BCE, whose kings built the great ziggurat of Ur and administered the land with famous bureaucratic thoroughness. When Ur fell to Elamites and Amorites around 2004 BCE, lamentation literature mourned the city as the gods' own decision, and spoken Sumerian faded within a few generations.
Its afterlife was extraordinary. For nearly two thousand years more, Babylonian and Assyrian scribes learned Sumerian as the language of liturgy and learning, copying hymns and lexical lists in it as European clergy would one day keep Latin; Stephanie Dalley's translations show how thoroughly Babylon inherited and reworked the Sumerian myths. Cuneiform's last dated tablet was written in the first century CE, and the decipherments of the nineteenth century recovered the whole tradition from the mounds of Iraq.