Parallel scaling of elite wealth in ancient Roman and modern cities with implications for understanding urban inequality

Abstract

Rapid urbanization and rising inequality are pressing global concerns, yet inequality is an ancient trait of city life that may be intrinsically connected to urbanism itself. Here we investigate how elite wealth scales with urban population size across culture and time by analyzing ancient Roman and modern cities. Using Bayesian models to address archeological uncertainties, we uncovered a consistent correlation between population size and physical expressions of elite wealth in urban spaces. These patterns suggest the presence of an ancient, enduring mechanism underlying urban inequality. Supported by an agent-based network simulation and informed by the settlement scaling theory, we propose that the observed patterns arise from common preferential attachment in social networks—a simple, yet powerful, driver of unequal access to interaction potential. Our findings open up new directions in urban scaling research and underscore the importance of understanding long-term urban dynamics to chart a course toward a fairer urban future. This study carries out a scaling analysis comparing the elite wealth concentration of ancient Roman cities with modern urban centers. It found that increased wealth concentration corresponds with increased population sizes across these cities despite being separated by millennia.