The name derives from Tell al-'Ubaid where the earliest large excavation of Ubaid period material was conducted initially in 1919 by Henry Hall, Leonard Woolley in 1922-1923, and later by Pinhas Delougaz in 1937.

During the Halaf-Ubaid Transitional (HUT), Ubaid and early Uruk periods, this developed into a climate characterised by stronger seasonal variation, heavy torrential rains, and dry summers.

Ubaid ceramics have been found from Mersin in the west to Tepe Ghabristan [d] in the east, and from Norşuntepe and Arslantepe in the north to Dosariyah in the south along the Gulf coast of Saudi Arabia.

Perhaps because such ancient settlements are buried deep under alluvial sediments, to date no archaeological site in southern Iraq has yielded remains older than Ubaid.

To resolve these issues, modern scholarship tends to focus more on regional trajectories of change where different cultural elements from the Halaf, Samarra, or Ubaid - pottery, architecture, and so forth - could co-exist.

Coastal sites where Ubaid pottery has been discovered include Bahra 1 and H3 in Kuwait, Dosariyah in Saudi Arabia, and Dalma Island in the United Arab Emirates.

Suggestions include foodstuffs (dates), semi-precious materials, jewellery (made from pearl and shell), animal products, and livestock.

Notably, the degree of cultural interaction between the Ubaid and local Neolithic communities is much stronger in the area of Kuwait than farther south, up to the point that it has been suggested that Mesopotamians may have lived for part of the year at sites such as H3 and Bahra 1.

For example, blades were made from a higher quality flint than other tools, and they may have been produced off-site, indicating that not only raw materials but also finished products were transported over larger distances.

For example, obsidian tools found along the Gulf coast at sites such as Dosariyah (Saudi Arabia) and Wadi Debayan (Qatar) came from sources in southeastern Turkey.

This may have been associated with the introduction of Canaanean blade technology, which became common in the fourth millennium BC that may have been linked to increased mass-production and intensification of agricultural strategies.

At southeastern Anatolian sites such as Değirmentepe and Norşuntepe, metallurgical production was practiced during the Ubaid 3, as evidenced by furnaces and related finds.

Ceramic boat models have been recovered from numerous sites across Mesopotamia, from Zeidan and Tell Mashnaqa in modern-day northern Syria to Eridu and 'Oueili in the south and Abada in the Hamrin.

Some of the earliest evidence comes in the form of an animal figurine from Iran dated to c. 5000 BC with incised decorations that might possibly represent wool.

The spindle whorls from Kosak Shamali, and also those from Telul eth-Thalathat II (northern Iraq), gradually decreased in weight, which could indicate that more and more finer-quality or softer fibers were spun.

By the time of the Ubaid period, a wide range of motifs had developed, including geometric patterns and depictions of animals and occasionally, humans.

The rarity of ophidian figures as grave gifts may indicate differential treatment of the dead, possibly based on age, kinship, or social standing.

In at least one case from southwestern Iran, a labret was found in situ in a burial, located at the mandible of the buried individual and with associated tooth wear indicating that it had been worn.

[33][45] The modern excavations at Tell Zeidan have revealed a wealth of information on the subsistence economy of a large northern Mesopotamian Ubaid settlement.

Domestic equipment included a distinctive fine quality buff or greenish colored pottery decorated with geometric designs in brown or black paint.

Villages thus contained specialised craftspeople, potters, weavers, and metalworkers, although the bulk of the population were agricultural labourers, farmers, and seasonal pastoralists.

[49] The Ubaid period in the south was associated with intensive irrigated hydraulic agriculture, and the use of the plough, both introduced from the north, possibly through the earlier Choga Mami, Hadji Muhammed, and Samarra cultures.

Morton Fried and Elman Service have hypothesised that Ubaid culture saw the rise of an elite class of hereditary chieftains, perhaps heads of kin groups linked in some way to the administration of the temple shrines and their granaries, responsible for mediating intra-group conflict and maintaining social order.

It would seem that various collective methods, perhaps instances of what Thorkild Jacobsen called primitive democracy, in which disputes were previously resolved through a council of one's peers, were no longer sufficient for the needs of the local community.

Whatever the ethnic origins of this group, this culture saw for the first time a clear tripartite social division among intensive subsistence peasant farmers, with crops and animals coming from the north, tent-dwelling nomadic pastoralists dependent upon their herds, and hunter-fisher folk of the Arabian littoral, living in reed huts.

Stein and Özbal describe the Near East oecumene that resulted from Ubaid expansion, contrasting it to the colonial expansionism of the later Uruk period.

Despite the fact that the Ubaid period is prehistorical, it has featured prominently in discussions on the origin and presence of the Sumerian and Akkadian languages in Sumer.

Based on this evidence, Henri Frankfort proposed in the 1930s that the people who wrote and presumably spoke Sumerian, originally came from the Iranian highlands and settled Mesopotamia at the start of the Ubaid period.

Speiser, on the other hand, thought that the Sumerians entered Mesopotamia during the Uruk period and interpreted the regional styles that existed before that time, i.e. Ubaid, Hassuna, Halaf, as evidence of distinct ethnic groups.

Archaeologists have stressed that a high degree of cultural continuity is evident throughout the Ubaid and Uruk periods, and it seems that there is some agreement that "the relation between three categories, linguistic, racial and ethnic, is exceedingly complex in Mesopotamia and still far from being sufficiently investigated".