Power and Size: Urban and Polity Size Swings and Changes in the Distribution of Power among States in Interstate Systems since the Bronze Age

Authors: Chase-Dunn, Christopher; Inoue, Hiroko
Journal: Social Evolution & History. Volume 16, Number 2 / September 2017


This study examines the temporal relationships between the growth and decline of cities and states and changes in the distribution of power among states in five whole interstate systems (world-systems) since 2700 BCE. World historians have long recognized that the population sizes of settlements and the territorial sizes of polities both increase over time and go through cyclical growth and decline phases. Earlier studies have found that urban and polity upsweeps (large increases in scale) are correlated in time. But the number of these instances of large-scale change (upsweeps) is few. More numerous are the smaller upswings in which the sizes of the largest city or polity increase but do not become significantly larger than earlier increases. Sweeps are large changes and swings are smaller changes. In this paper we will study these more numerous urban and polity swings in five political-military interaction networks (PMNs) in which we have enough size estimates to study changes in the sizes of the largest cities and empires. We will compare swings with sweeps to see if there are patterned differences. The political military networks or interstate systems that we will study are those located and centered in Mesopotamia, Egypt, East Asia, South Asia and the expanding Central PMN1 since 1500 BCE.2 Thus, the main unit of analysis in this paper is the political/military interaction network. We will study the relationships across time between city and empire growth and decline in each of these interstate networks and we will examine the relationships between these and changes in the power configuration of these same systems. Interstate power configurations vary from decentralized to centralized based on the relative sizes and power of the in-teracting states in each system. We will also discuss such potential causes of upswings and upsweeps as demographic change, warfare and trade. And we will consider whether or not the causes of downswings are different from the causes of upswings.