Replication data for: Regime Type, Coalition Size, and Victory

Studies of regime type and war show that democracies tend to win the wars they fight, but questions remain about why this is the case. A simple, if under-appreciated, explanation for democratic success is that democracies fight alongside larger and more powerful coalitions. Coalition partners bring additional material capabilities and may also provide intangible benefits to the war effort, such as increased legitimacy or confidence. Democracies may also find it less costly to join coalitions, as democratic war aims may be easier to apportion among the victors without diluting the spoils. Evaluating our hypotheses in a sample of all wars (or all militarized disputes) during the period 1816-2000, we find that democracies fight alongside larger coalitions and that states fighting alongside larger coalitions are more likely to win major contests. Coalition size subsumes most (and in some specifications all) of the direct effect of regime type on victory.