Remains of the worlds first cities are the most noteworthy features of the landscape in southern Iraq, and for nearly two centuries archaeologists have probed them and puzzled over their artifacts. Built up over the course of five and a half millennia of intermittent occupation, these tells--mounds of building rubble and associated artifacts--can be as large as a mile in diameter; some rise more than 100 feet above the plain. Babylon, Ur, Uruk, Nippur and Kish have yielded abundant evidence of the material culture of Mesopotamian society. Thanks to their citizens relatively imperishable writing medium--clay tablets--they have also provided detailed textual testimony on political, intellectual, religious and social institutions.
Nevertheless, the physical and social organization of these most ancient cities is still poorly understood, for a variety of reasons. Paradoxically, the very richness of evidence has led to ignorance. The tells are so massive that even the best-financed field parties can excavate only tiny fractions of each city. More important, the arrangements of buildings that archaeologists uncover generally do not represent a city that actually existed at one particular time. The ancient inhabitants built on earlier structures in some cases and swept them away or modified them in others. One might imagine a similar problem facing archaeologists trying to understand London a few thousand years hence: they would be confronted by the mixed remains of modern skyscrapers, Victorian buildings, Norman castles and even a Roman garrison; reconstructing the city as it looked during any given period would be almost impossible.
Urban sociologists have long known that the plans of contemporary cities reflect patterns of social organization. Our own survey of non-Mesopotamian early cities shows that similar conclusions can be drawn about early urban sites. Where power is highly focused and based on coercion, centers of administration, religion, manufacture and trade cluster together, surrounded by residences of the elite. In contrast, societies in which diverse groups share control and in which decision making takes place at various levels of the social hierarchy show little or no evidence of such concentration. The intimate ties between elites and the rest of the population in these decentralized cities are mirrored by a mixture of rich and poor houses in each of the residential districts.
Where are humankinds first cities to be placed in this spectrum? Archaeologists have tended to emphasize centralization, but a close look at their reasoning, combined with our recent findings at a site called Mashkan-shapir, indicate that this view needs revision. Early excavations in Mesopotamia focused on seats of wealth and power--palaces and temples--and led researchers to take a similarly narrow view in reconstructing the society that built them. Yet concentration on the physical remains of high status obscured the fact that Mesopotamian texts do not identify clearly differentiated social classes. Instead they record the importance of general assemblies in decision making.
There may also be a more subtle bias at work. Historians recognize that industrialism and capitalism have so transformed the world that there are no modern analogues for ancient cities. Rather than considering a wide range of potential urban organizations, however, some scholars have perhaps too readily posited a unified model for a "preindustrial city" based on a few, well-studied (and centralized) examples. In devising this model they have rarely looked further afield than ancient Greece and sometimes no further than medieval Europe.
As a result, researchers have in effect taken for granted that cities in Mesopotamia were shaped by the same forces as were later European ones, among them a stable agricultural base and a fixed value for any given plot of land. In fact, the economic base in this region was anything but geographically stable--as indicated by the importance of nomadic herding. Even cultivated land was impermanent: annual floods, high evaporation rates and rapid poisonous salinization of land under cultivation led to a constantly shifting mosaic of rich irrigated fields and orchards, deserts and marshes, in which wealth or power had little to do with permanent control of a particular parcel. Detailed descriptions of many preindustrial urban civilizations--in West Africa, the Islamic Middle East and the New World at the time of the conquistadors--show considerable variability in organization; they also suggest a link between the permanence of agricultural land and the degree of social and political centralization. There is thus no reason to assume a priori that Mesopotamian cities were especially centralized.