Measuring Multidimensional Inequality and Its Impact on Civil War Outbreak in 193 Countries, 1810–2010

We construct an index of composite inequality covering 193 countries worldwide. For a substantial and unprecedented number of countries, we can trace the long‐term evolution of inequality over 200 years, from 1810 to 2010. This composite index of inequality includes not only post‐tax income inequality but also health and land inequalities. We observe that the risk of a civil war outbreak is consistently increasing with higher levels of within‐country inequality. By applying an instrumental variable approach, we discover that the impact of multidimensional inequality on civil war is causal. This finding is not only relevant for unstable low‐ and middle‐income countries like Chad or South Sudan but also has implications for high‐income countries, such as the United States and the United Kingdom, for which we predict an increased likelihood of civil war.