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Unequal We Fight: Between- and Within-Group Inequality and Ethnic Civil War*

  • Patrick M. Kuhn and Nils B. Weidmann

When and why ethnic groups rebel remains a central puzzle in the civil war literature. In this paper, we examine how different types of inequalities affect both an ethnic group’s willingness and opportunity to fight. We argue that political and economic inter-group inequalities motivate ethnic groups to initiate a fight against the state, and that intra-group economic inequality lowers their elite’s costs of providing the necessary material and/or purposive incentives to overcome collective action problems inherent to rebel recruitment. We therefore predict that internally unequal ethnic groups excluded from power and/or significantly richer or poorer relative to the country’s average are most likely to engage in a civil war. To assess our claim empirically, we develop a new global measure of economic inequality by combining high-resolution satellite images of light emissions, spatial population data, and geocoded ethnic settlement areas. After validating our measure at the country- and group level, we include it in a standard statistical model of civil war onset and find considerable support for our theoretical prediction: greater economic inequality within an ethnic group significantly increases the risk of conflict, especially if political or economic inequalities between groups provide a motive.

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Patrick M. Kuhn, Lecturer in Comparative Politics, School of Government and International Affairs (SGIA), Durham University, Durham, UK ( Nils B. Weidmann, Professor of Political Science, Department of Politics and Public Administration, University of Konstanz, Konstanz, Germany( The authors thank Danielle F. Jung, Jacob N. Shapiro, Thomas Scherer, Austin Wright, and seminar participants at the 3rd Annual Conference of the European Political Science Association, the Princeton International Relations Faculty Colloquium, the Mannheim Center for European Social Research, the Peace Research Institute Oslo, as well as the anonymous reviewers for their helpful comments. This research was supported, in part, by AFOSR, grant # FA9550-09-1-0314 and by the Alexander von Humboldt Foundation (Sofja Kovalevskaja Award). A large part of the writing was completed while the first author was a Postdoctoral Associate at the Woodrow Wilson School for Public and International Affairs at Princeton University. The data used in this study are available via the PSRM DataVerse site. To view supplementary material for this article, please visit

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