The Ubaid expansion, from the South to the North of Mesopotamia should no longer be understood as a colonization of Southern Ubaid communities. The diffusion of Ubaid, from the middle of the 6th millennium to the end of the 5th, is a complex process, defined by G. Stein as “global” and “local” phenomenon. If this transformation is clearly demonstrated in Northern Mesopotamia with a so-called Halaf-Ubaid transitional period, especially with ceramic evidences, our study on architecture extends this issue to peripheral regions such as Southern Caucasus where intensive research is carried out for several years on Chalcolithic.

The adoption of Ubaid architectural techniques in Northern Mesopotamia is characterised by the spread of standardised moulded mud-brick, complex bonds and tripartite plans. Nevertheless, local techniques, as cob and stone foundations, persist in Northern Mesopotamia where Ubaid culture appears, proof of maintaining of technical and cultural traditions. In Southern Caucasus, Chalcolithic level at Mentesh Tepe (4300-4100 BC) is related to a tripartite building possibly linked with an intrusion of northern Mesopotamian origin. As in Northern Mesopotamia, the weight of tradition is strong in Mentesh Tepe as evidenced by the variability of moulded mud-brick sizes and simplicity of bonds, distinct to Ubaid techniques.

The aim of this paper is to show that the Ubaid expansion is reflected in architecture by a complex phenomenon: a general adoption of new techniques in the Northern regions, but also by the adaptation of Ubaid architecture to local “pressures”. New data provided from Southern Caucasus, on the fringe of the Ubaid expansion, complete this overview on the correlation between transmission and assimilation of architectural techniques and social mechanisms.