After the discovery in Syria of the sites at [[Habuba Kabira]] and {{interlanguage link|Jebel Aruda|fr|Djebel Aruda}} in the 1970s, they were identified as colonies or trading posts of the Uruk civilisation settled far from their own lands. Indeed these two sites, along with the smaller site of [[Tell Sheikh Hassan]], feature no significant preexisting occupation, and are in fact all located in the same geographical area at a significant river ford along the Middle Euphrates.

 

 

Later, questions arose about the relationship between Lower Mesopotamia and the neighbouring regions. The fact that the characteristics of the culture of the Uruk region are found across such a large territory (from northern Syria to the Iranian plateau), with Lower Mesopotamia as a clear centre, led the archaeologists who studied this period to see this phenomenon as an "Uruk expansion". This has been reinforced by the political situation in the modern Near East and the impossibility of excavating in Mesopotamia. Recent excavations have focused on sites outside Mesopotamia, as a 'periphery', and with an interest in how they related to the 'centre', which is paradoxically the region in this period which is least well-known—limited to the impressionistic discoveries of the monuments of Uruk. Subsequently, theories and knowledge have developed to the point of general models, drawing on parallels from other places and periods, which has posed some problems in terms of getting the models and parallels to fit the facts revealed by excavations.<ref name=histo/>