In this Quantitative History Webinar, Patrick Fitzsimmons of the University of Pennsylvania will present a theory of how lowering the cost of doing violence around 1200 BCE contributed to political fragmentation across the Eastern Mediterranean. He points out that bronze’s reliance on scarce tin concentrated the means of violence among elites, supporting large, centralized empires, while the widespread availability of iron redistributed weapons access to non-elites and weakened elite dominance. Using novel century-level shapefiles of ancient Eastern Mediterranean polities, Patrick exploits staggered iron adoption across 200 km × 200 km grid cells in a two-way fixed-effects framework, finding that iron adoption increases polities per cell by approximately 1.47–1.52 units. An instrumental-variable approach roughly doubles this estimate, and analyses of bronze show the opposite effect. A range of alternative specifications and explanations are tested; all point toward iron’s fragmenting effect.

Discussant: Senhao Hu, PhD student, Hong Kong Institute for the Humanities and Social Sciences (IHSS)