The earliest civilizations in the three regions of our concern have been termed Sumerian (Mesopotamia), Namazga (Central Asia), and Harappan (Indus Valley). Archaeologists, almost as one, hold firm to the conviction that each of the above civilizations is at least partly the result of an indigenous, autonomous process of development. In each case the distinctive nature of their material remains, their geographical separation, and most particularly the differing cultural traditions so apparent in the material culture that characterized each area prior to the emergence of urban complexity provide substantial support for their indigenous emergence. This is not to say, however, that particular forms of social relations, particularly of a commercial nature, did not provide an integrative force with their adjacent frontiers. The chronological priority of the Sumerian civilization over the Harappan is simply not sufficient for claiming that “it can at least be averred that, however translated, the idea of civilization came to the Indus from the Euphrates and Tigris, and gave the Harappans their initial direction, or at least informed their purpose” (Wheeler 1968b: 135).