The Ubaid period (c. 6500–3800 BC) is a prehistoric period of Mesopotamia. The name derives from Tell al-'Ubaid where the earliest large excavation of Ubaid period material was conducted initially by Henry Hall in 1919, Leonard Woolley in 1922–1923, and later by Pinhas Delougaz in 1937.H. R. Hall, "Season's Work at Ur; Al-'Ubaid, Abu Shahrain (Eridu), and Elsewhere; Being an Unofficial Account of the British Museum Archaeological Mission to Babylonia, 1919", Methuen, 1930P. Delougaz, "A Short Investigation of the Temple at Al-'Ubaid", Iraq, vol. 5, pp. 1–11, 1938 Excavations continue to the present day.

In Southern Mesopotamia, this period marks the earliest known settlements on the alluvial plain, although evidence of earlier habitation has likely been obscured under the alluvium. In the south the Ubaid period spans from about 5500 to 3800 BC, when it is succeeded by the Uruk period.

In Northern Mesopotamia the period runs only from about 5300 to 4300 BC. It is preceded by the Halaf period and the Halaf-Ubaid Transitional period, and succeeded by the Late Chalcolithic period.

History of research The excavators of Eridu and Tell al-'Ubaid found Ubaid pottery for the first time in the 1910–1920s. In 1930, the attendees at a conference in Baghdad defined the concept of an "Ubaid pottery style". The characteristic pottery of this style was a black-on-buff painted ware. This conference also defined the Eridu and Hajji Muhammed styles. Scholars at this conference mistakenly thought that these pottery styles were so different that "[...] they could not have developed out of the old, as is the case with the Uruk ware after the al-'Ubaid ware [...]". For many attendants of the conference, "this sequence based largely on pottery represented a series of different 'ethnic elements' in the occupation of southern Mesopotamia." These ideas about the nature of the Ubaid style phenomenon did not last. The term "Ubaid" is still used, but its meaning has changed over time.

Joan Oates demonstrated in 1960 that the Eridu and Hajji Muhammed styles were not distinct at all. Instead, they were part of the greater Ubaid phenomenon. She proposed a chronological framework that divides the Ubaid period in four phases. Other scholars later proposed two more phases, zero and five.

Scholars in the 1930s only knew a few Ubaid sites. These included the type site of Tell al-'Ubaid, Ur, and in the north, Tepe Gawra. Since then, archaeologists have discovered Ubaid material culture throughout the ancient Near East. There are now Ubaid sites in the Amuq Valley in the northwest and all the way to the Persian Gulf coast in the southeast. Important research includes the many excavations in the Hamrin area in the 1970s. There, archaeologists found a complete Ubaid settlement at Tell Abada, and a very well-preserved house at Tell Madhur. The excavation at Tell el-'Oueili in the 1980s revealed occupation layers that were older than those from Eridu. This discovery pushed back the date for the earliest human occupation of Lower Mesopotamia.

Excavations along southern coast of the Persian Gulf provided a great deal of evidence for contacts with Mesopotamia. The site of H3 in Kuwait, for example, provided the earliest evidence in the world for seafaring. The explosion of archaeological research in Iraqi Kurdistan since the 2010s also led to discovery of even more new data on the Ubaid. For example, this research demonstrated that cultural links between the Shahrizor Plain and the Hamrin area farther south were stronger than those with the north.

Climate and environment

Mesopotamia lacks local, high-resolution climate proxy records such as those found at the Soreq Cave in Israel, making it difficult to reconstruct the region's past climate. Even so, it is known that the environment during the sixth and fifth millennium BC differed from today's. A more temperate climate settled in around 10,000 BC. Marshy and riverine areas transformed into floodplains, and eventually river banks with trees. The area south of Baghdad may have been habitable by humans in the eleventh millennium BC, but current evidence places the earliest settlements south of Uruk during the eighth millennium BC, though previous scholarship had believed it to be much later.

Archaeobotanical research in the Ubaid 0 levels at 'Oueili (6500-6000 BC) has indicated the presence of Euphrates poplar and sea clubrush, both indicating a wetland environment. Changes in sea-level shaped the shoreline of the Persian Gulf: at the beginning of the Ubaid, around 6500 BC, the shoreline at Kuwait may have run slightly farther south. During the subsequent 2.5 millennia, the shoreline moved farther northward, up to the ancient city of Ur around 4000 BC.

Date palms were present in southern Mesopotamia since at least the eleventh millennium BC, predating the earliest evidence for domesticated dates from Eridu by several millennia. Date palms require a perennial water source, again indicating that this period may have been wetter than today. Similarly, oak was present from the eighth millennium, but disappeared at around the same time that Ubaid material culture spread outward from southern Mesopotamia during the sixth millennium BC. It has been suggested that acquisition of high-quality wood may have played a role in this expansion.

The available evidence in northern Mesopotamia points to a cooler and drier climate during the Hassuna and Halaf periods. From the Halaf-Ubaid Transitional (HUT) to early Uruk periods, this developed into a climate characterised by stronger seasonal variation, heavy torrential rains, and dry summers.

Dating and geographical distribution Ubaid and Ubaid-like material culture has been discovered over an immense area. Ubaid ceramics have been found from Mersin in the west to Tepe Ghabristan in the east, and from Norşuntepe and Arslantepe in the north to Dosariyah in the south along the Gulf coast of Saudi Arabia. In this area, researchers have discerned considerable regional variation, indicating that the Ubaid was not a monolithic culture through time and space.

Currently, the Ubaid period is most commonly divided in six phases, called Ubaid 0–5, with the oldest known site in southern Mesopotamia (Tell el-'Oueili) dating to Ubaid 0. Some of these phases denote pottery styles previously considered distinct from Ubaid, but which are now considered to be part of the same culture. Some of these styles, such as those found at the type site of Hadji Muhammed (previously equated with Ubaid 2) are now known to occur also in Ubaid 3 contexts, thereby limiting their value as chronological markers. The relative chronology is based on the long stratigraphic sequences of sites such as Ur, Eridu, and Tepe Gawra. The absolute chronology is more difficult to establish, mainly due to a lack of abundant radiocarbon dates determined in southern Mesopotamia. +Relative Ubaid chronologyphasealternative nameNorthern Mesopotamiadate (BC) (after Pournelle 2003 / after Harris 2021)Ubaid 0Oueili phaseEarly Pottery Neolithic6500–5900 / 6800–6200Ubaid 1Eridu styleHalaf5900–5200 / 6200–5500Ubaid 2Hadji Muhammad styleHalaf-Ubaid Transitional5200–5100 / 5500–5200Ubaid 3Tell al-'Ubaid styleNorthern Ubaid5100–4900 / 5200–4600Ubaid 4Late UbaidNorthern Ubaid4900–4350 / 5200–4600Ubaid 5Terminal UbaidLate Chalcolithic 14350–4200 / 4600–4200

Southern Mesopotamia

In the south, corresponding to the area that would later be known as Sumer, the entire Ubaid period extends from ca. 6500 to 3800 BC. It is here that the oldest known Ubaid site, Tell el-'Oueili, was discovered. To date no archaeological site in southern Iraq has yielded remains more ancient than Ubaid, though they might exist buried deep under alluvial sediments. This was the case, for example, of the site of Hadji Muhammed, which was discovered only by accident.

Central and northern Mesopotamia

In central and northern Iraq, the Ubaid culture was preceded by the Hassuna and Samarra cultures. The Ubaid may have developed out of the latter. In Northern Syria and southeastern Turkey, the Ubaid follows upon the Halaf period, and a relatively short Halaf-Ubaid Transitional period (HUT) dating to c. 5500-5200 BC has been proposed as well. HUT pottery assemblages displayed both typically Ubaid and Halaf characteristics. The relationships between these cultural periods is complex and not yet fully understood, including how and when the Ubaid began to appear in Northern Mesopotamia. 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. This makes it increasingly difficult to define an occupation phase at a site as, for example, purely Ubaid or purely Halaf.

In Northern Mesopotamia, Ubaid characteristics only begin to appear in Ubaid 2-3, i.e. toward the end of the sixth millennium BC, so that the entire Ubaid period there would be much shorter. For Syria, a range of 5300–4300 BC has been suggested. However, some scholars have argued that the interaction between the originally southern Mesopotamian Ubaid and the north had begun during Ubaid 1–2.

Persian Gulf

Ubaid pottery began to appear along the Persian Gulf coast toward the end of the sixth millennium BC, reaching a peak around 5300 BC and continuing into the fifth millennium. 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. Ubaid pottery has also been found further inland along the central Gulf coast at sites such as Ain Qannas, suggesting that the pottery may have been a valuable trade item, rather than being a container for some other commodity. This suggestion is reinforced by locally-produced pottery imitating Ubaid wares found at Dosariyah. It is unclear which products were traded for the pottery. 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 further 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. Small objects such as labrets, tokens, clay nails, and small tools that may have had cosmetic use, and that are known from southern Mesopotamian sites also occur on sites along the Gulf coast, notably the sites in Kuwait.

Conversely, evidence exists for Arabian Neolithic material in Southern Mesopotamia. It has been noted that certain types of flint arrowheads found at Ur show clear resemblance with the Arabian Bifacial Tradition. Arabian Coarse Ware has been found at the sites of 'Oueili and Eridu. As at the sites in Kuwait, it may be possible that Arabian Neolithic groups also lived in Southern Mesopotamia.

Material culture

Figurines