(1) An Aeneolithic archaeological culture widespread in southern Mesopotamia in the fourth millennium B.C. It was named for the characteristic finds excavated in levels XIV to IV at the ancient city of Uruk (Erech; see below). It was preceded by the Ubaid (Ubayd or Obeid) culture, which is represented at Uruk in earlier levels, namely levels XVIII to XV.

The Uruk culture was characterized by wheel-made red and gray pottery and by developed metallurgy. During this period, cylinder seals (level X) appeared, as well as pictographic documents on clay tablets (level IV), the oldest such Sumerian documents. Monumental buildings made of mud bricks were erected, including the Red Building (possibly a place for popular assemblies) and the White Temple, both located in the main part of the city. The population engaged in land cultivation and stock raising. The period was characterized by a decline of the primitive-communal system and the emergence of elements of a class society, which developed further during the next stage (end of the fourth millennium B.C.), a stage characterized by finds of the Jemdet Nasr type (level III of Uruk and elsewhere).

(2) An ancient city-state in Sumer (Sumerian Uruk; biblical Erech; Greek Orchoe). In the 28th and 27th centuries B.C., under the semilegendary rulers Enmerkar, Lugalbanda, and Gilga-mesh, about whom epic tales have been preserved, the city-states of southern Mesopotamia were united under the hegemony of Uruk (First Dynasty of Uruk). In the 24th century B.C., under Lugal-zaggesi, Uruk became the capital of Sumer. After its capture by Sargon I the Ancient (24th century B.C), it became part of his kingdom. At the end of the 22nd century, Utu-khegal, the king of Uruk, formed the united Kingdom of Sumer and Akkad in Mesopotamia. After his death, the throne passed to Ur-Nammu, founder of the Third Dynasty of Ur. Uruk remained an important city until the end of the first millennium B.C. In the eighth to second centuries B.C, it was an autonomous temple city, first in the Babylonian kingdom and later in the Achaemenid and Seleucid kingdoms. It was destroyed by the Sassanids in the third century A.D.

The village of Tall al-Warka is now located at the site of Uruk, 65 km northwest of the city of al-Nasiriyah. Systematic excavations have been conducted since the early 20th century by German expeditions, one of which was headed by J. Jordan and one by A. Neldeke and H. Lenzen (Federal Republic of Germany).