Which type of international organizations can settle civil wars?

Abstract

International organizations (IOs) take on an increasing share of civil war mediation around the world. The determinants of IO mediation effectiveness remain poorly understood, partly because prior research has not adequately captured the institutional heterogeneity of peace-brokering IOs. To explore how mediation effectiveness depends on institutional variation, I combine newly gathered data on the design of 13 peace-brokering IOs with existing data on 109 civil war mediation episodes in the 1975-2004 period. I find that IOs with institutionalized capabilities to deploy field missions, such as peacekeeping operations, outperform other IOs as mediators of civil wars, whereas information-gathering capacity does not yield a significant advantage. The results suggest that IO enforcement assistance has a forward-looking effect: the ability to credibly signal, ex ante, that peacekeeping or monitoring forces will be deployed to enforce an agreement, helps IOs shape negotiations long before forces are actually deployed. Reaffirming the credible commitment theory of conflict resolution, the study demonstrates that there is considerable variation among external guarantors, which explains why some IOs can shift civil war disputants away from violent bargaining strategies whereas other cannot.