The neo-evolutionist approach is well illustrated by †J.H.Steward (1955), who attempted to reconstitute the different stages from *hunter-gatherer †bands to the formation of the state. The emphasis here is on the role of irrigation which allows a large concentration of population and therefore leads to more elaborate territorial organization, requiring a new division of labour and a more developed power structure. For Steward, as for the historian †K.Wittfogel (1957), the expansion of the † hydraulic economy would have been a determining factor in the invention of the state. Starting from †Marx’s arguments on the †‘Asiatic mode of production’, Wittfogel showed that the absence of private property in *peasant societies is entirely compatible with the development of a substantial political and administrative apparatus. Morton Fried (1967) distinguished four successive stages-egalitarian societies, class societies, stratified societies and state societies. For Fried the decisive factor in the transition to stratified societies and the emergence of the state is the fact of unequal access to resources due to demographic pressure within the limits of a given territory.