The Ubaid culture, which is characterised by a distinctive type of pottery, originated on the flat flood plains of southern Mesopotamia in around 5900 BC. It was during this period that the first identifiable farming and fishing villages developed in the region. Some settlements developed into towns which were often focused on monumental buildings, perhaps temples, such as at Eridu and Uruk. The dead were sometimes buried with distinctive clay figurines.

The Ubaid culture spread across Mesopotamia gradually replacing the Halaf culture in the north and as far west as the Levant. Ubaid pottery is also found to the south of Mesopotamia, along the coasts of the Persian Gulf at sites which relied heavily on fishing. During this period there was an increase in the variety of seal designs to include animals with humans, and snakes and birds. There is much continuity between the Ubaid culture and the succeeding Uruk period when many of the earlier traditions were developed, particularly in architecture.