The city was founded in the prehistoric Ubaid Period (c. 5200–c. 3500 BC) and was still occupied as late as the Parthian era (247 BC–AD 224). In the Early Dynastic Period the rulers of Lagash called themselves “king” (lugal), though the city itself never was included within the official Sumerian canon of kingship. Among the most famous Lagash monuments of that period is the Stele of the Vultures, erected to celebrate the victory of King Eannatum over the neighbouring state of Umma. Another is the engraved silver vase of King Entemena, a successor of Eannatum. Control of Lagash finally fell to Sargon of Akkad (reigned c. 2334–2279 BC), but about 150 years later Lagash enjoyed a revival. It prospered most brilliantly under Gudea, who was probably a governor rather than an independent king and was nominally subject to the Guti, a warlike people who controlled much of Babylonia from about 2230 to about 2130.

Lagash was endowed with many temples, including the Eninnu, “House of the Fifty,” a seat of the high god Enlil. Architecturally the most remarkable structure was a weir and regulator, once doubtless possessing sluice gates, which conserved the area's water supply in reservoirs.