68 Pages Posted: 16 Dec 2016 Last revised: 27 Apr 2020

Date Written: April 27, 2020

Abstract

The origins and global variation of democratic political institutions are not well understood. This study tests the hypothesis that the Catholic Church’s medieval prohibition on kin marriages fostered participatory institutions by dissolving strong extended kin networks. First, I show that weak pre-industrial kin networks are positively associated with countries’ democracy scores. At the same time, medieval Church exposure robustly predicts weak kin networks across countries, European regions and ethnic societies. In a difference-in-difference analysis, I then provide historical evidence that exposure to the Church fostered the formation of medieval communes – self-governed cities with participatory institutions that many scholars have identified as critical precursors for national parliaments. Moreover, within medieval Christian Europe, stricter regional and temporal cousin-marriage prohibitions are associated with increased formation of commune cities. Lastly, I shed light on one mechanism, civicness, and show that weak kin networks are associated with higher political participation.