Some horticultural societies of the past developed more intensive agricultural subsistence patterns when their populations grew into the thousands.  As this interrelated economic and populational transition occurred, they were forced to create a new level of political integration in order to maintain unity and order.  This was the chiefdom and ultimately the state.  This marks the beginning of centralized, fulltime leadership and nonegalitarian societies.  Before examining the nature of chiefdoms and states, it is important to keep in mind that the political systems in many societies do not clearly fit either category completely.  They are essentially in transition from tribes to chiefdoms or from chiefdoms to states.

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City States Preceded Nation States
Nation State: Fundamental Unit of State Power