This article is based mainly on archaeological surveys of the Iraqi Directorate General of Antiquities between the years 1938–1965. In preparing this study, the writer examined more than 7,000 files in the Directorate's archives. The reliability of the report on each site has been carefully assessed. The numbers following the site names indicate serial numbers of relevant files in the Directorate's archives. The name of the district (Qadha or Nahiya) in which a site is located usually follows the serial number.
Examination of the available surface material from all over Iraq, suggests that Uruk pottery is more popular in the north than the south. It is not possible at present to tell whether this fact is significant, as the existing southern surveys are far from complete. Moreover, in the south there is the added problem of silting and subsidence which would have tended to obliterate sites, in particular small ones, of Uruk and earlier dates. However, where extensive surface surveys have been carried out, as, for example, in the Diyala and Nasiriya Liwas, and now in the Eridu and Warka regions, a number of Uruk sites has been found. In spite of the smaller number of recorded sites, one is inclined to treat the south as the focal area at this time, owing to the social and urban development which is known to have taken place there, and for which we have no parallels as yet in the north. However, only further excavations in the north and further survevy in the south can satisfactorily resolve these problems.