<Dd> <Ul> <Li> Carneiro's circumscription theory </Li> </Ul> </Dd> <Ul> <Li> Carneiro's circumscription theory </Li> </Ul> <Li> Carneiro's circumscription theory </Li> <Dl> <Dd> Main article: Carneiro's circumscription theory <Dl> <Dd> Robert Carneiro developed a theory (1970) aiming to provide a more nuanced understanding of state formation by accounting for the fact that many factors (surplus agriculture, warfare, irrigation, conquest, etc .) did not produce states in all situations . He concluded that while population pressure and warfare were mechanisms of state formation, they only created states in geographic regions circumscribed, or walled off from the surrounding area . Geographic barriers (or in some cases barriers created by nomadic raiders or by rival societies) create limitations on the ability of the people to deal with production shortfalls, and the result is that warfare results in state creation . In situations of unlimited agricultural land (like the Amazon or the Eastern United States), Carneiro believes that the pressures did not exist and so warfare allowed people to move elsewhere and thus did not spur creation of a state . </Dd> </Dl> </Dd> </Dl>

What factors contributed to state building in africa