This paper considers how coups d’état influence the duration of civil wars. While previous work on civil war duration has ignored coups, grouped them alongside civil wars or considered them as a special type of conflict, this article recognizes coups as dramatic events that can quickly change the course of a conflict. Coups that take place during a civil war can shock an otherwise intractable bargaining situation, shortening the war’s duration. This shock influences both information and credibility concerns. Coups condense government preferences into a single, unified viewpoint and allow governments to efficiently translate preferences into action. They likewise combine the military with the government, effectively eliminating the military as a potential spoiler, which helps ease the commitment problem. These expectations are tested by examining the impact of successful coups on civil war duration, 1950–2009. Results suggest that coups indeed serve as peace-inducing shocks, primarily by working through the credibility mechanism.