This thesis is a discussion of ideology, social space and power in Uruk societies from 4000 to 3000 B.C. The focus is on the interaction between north and south during the Uruk expansion, in which the northern areas became influenced by south Mesopotamian culture. I argue that the social ideology of these societies are reflected in their material culture, and that this aspect was important during the period. It is also important for understanding how the trading connections in the region developed.