Europe was the last to become civilized.
Aryans likely started out around Iran or India, and slowly migrated northwest, to Europe eventually.
The Celts for example, ended up in Spain and Ireland.
But they did not end their nomadic ways and start building permanent structures until the Roman occupations.
In comparison, those of the Mideast were thousands of years ahead of Europe.
{...
Small domes in corbelled stone or brick over round-plan houses go back to the
Neolithic period in the
ancient Near East, and served as dwellings for poorer people throughout the
prehistoric period, but domes did not play an important role in monumental architecture.
[15] The discoveries of
seal impressions in the ancient site of
Chogha Mish (c. 6800 to 3000 BC), located in the
Susiana plains of
Iran, in the vicinity of the modern city of Dezful in Khuzestan province, show the extensive use of dome structures in mud-brick and
adobe buildings, likely granaries.
[16] Other examples of mud-brick buildings that also seemed to employ the "true" dome technique have been excavated at
Tell Arpachiyah, a Mesopotamian site of the
Halaf (c. 6100 to 5400 BC) and
Ubaid (ca. 5300 to 4000 BC) cultures.
[17] Excavations at
Tell al-Rimah have revealed pitched-brick domical vaults from about 2000 BC.
[18]
At the
Sumerian Royal Cemetery of
Ur, a "complete rubble dome built over a timber centring" was found among the chambers of the tombs for
Meskalamdug and
Puabi, dating to around 2500 BC.
[19] Set in mud mortar, it was a "true dome with pendentives rounding off the angles of the square chamber." Other small domes can be inferred from the remaining ground plans, such as one in the courtyard of
Ur-Nammu's ziggurat, and in later shrines and temples of the 14th century BC.
[20] Some monumental Mesopotamian buildings of the
Kassite period are thought to have had brick domes, but the issue is unsettled due to insufficient evidence in what has survived of these structures.
[15]
A
Neo-Assyrian bas-relief from
Kuyunjik depicts domed buildings, although remains of such a structure in that ancient city have yet to be identified, perhaps due to the impermanent nature of sun-dried
mudbrick construction.
[21][22] However, because the relief depicts the Assyrian overland transport of a carved stone statue, the background buildings most likely refer to a foreign village, such as those at the foothills of the
Lebanese mountains. The relief dates to the 8th century BC, while the use of domical structures in the
Syrian region may go back as far as the fourth millennium BC.
[23] Likewise, domed houses at
Shulaveri in
Georgia and
Khirokitia, Cyprus, date back to around 6000 BC.
...}