As discussed in Chapters 1 and 2, mankind moved away from its initial condition of equality in three broad steps. Men and women invented technologies of production that eventually led to growing economic differences across individuals and territories. That economic inequality resulted in the breakdown of a collective order based on the nonformalized, horizontal application of rewards and sanctions to generate social compliance. Individuals, now competing systematically over the control of highly productive patches, set up formal (state) institutions to control, defend, and exploit their economic resources. In this new world, the conduct of war became a key determinant of the structure of those institutions. The nature and complexity of military technologies affected the power of producers (vis-à-vis those individuals that specialized in the exercise of violence) and determined the size and scope of the state. They shaped also the final level of inequality because the distribution of political power often modified the distribution of resources given by the existing technologies of production.

This chapter and the following two put the main hypotheses of the book to an empirical test. Chapter 3 examines how technological change and a correlated spatial clustering of productive resources led to the emergence of territorial and interpersonal inequalities, the formation of social hierarchies, and the creation of state institutions. Chapter 4 deals with the impact that specific war technologies had on the distribution of political power within states. Chapter 5 explores the effect of both technological changes and military power on inequality.