This chapter examines the causes, prosecution, outcomes, and consequences of civil wars. It defines the concept of civil war, distinguishes between nationalist and secessionist civil wars, and presents several factors thought to drive civil war onset, including grievance, relative deprivation, identity, lootable resources, and state capacity. It then examines factors that might affect the likelihood of ending civil wars once started, including whether the issues under dispute are seen to be indivisible and the severity of commitment problems. It describes the consequences when rebel groups fighting a civil war are fragmented, and relatedly when there are several actors fighting in a civil war. The chapter then lays out possible solutions for ending civil wars and creating lasting peace, including third-party guarantors, power-sharing, and creating integrated police and security forces. It then discusses some of the devastating human consequences of civil wars The chapter applies many of the concepts in the chapter to a quantitative study on whether peacekeepers help prevent civil wars from recurring, and a case study of the Syrian Civil War.

This chapter explores third-party mediation and peacekeeping. Mediation, along with arbitration and adjudication, is a form of peacemaking. Peacekeeping means maintaining durable peace after conflict has ended. The UN is one of several kinds of actors that engage in peacekeeping missions. They leverage the costs belligerents would pay if they return to war, provide information, reduce uncertainty, and provide political cover to facilitate political concessions. Also discussed in the chapter are peacebuilding efforts, including developing the proper political, legal, social and economic infrastructure to stabilize the security environment. Challenges for third parties seeking to engage successfully in peacekeeping and peacemaking include the difficulties they face in providing long-term incentives for peace, the possibility of distorting information flows such that peace is less stable, and being sensitive to local contexts. The chapter applies many of its concepts to a quantitative study of the causes of peacekeeper sexual exploitation and abuse, and a case study of third-party involvement during the conflicts in the Great Lakes region of Africa in the 1990s and 2000s.

War, sadly, has always been part of human affairs, however much poets and ordinary people from antiquity onwards have longed for the blessings of peace. From earliest times states have allied with each other, promising not to make war on each other and, often, to defend the other from attack. The subject of this volume, however, is not peace but peacekeeping: the use of members of armed forces (as well as police and other civilians), working in a multinational environment in the wake of conflict, helping bring about conditions that will allow the parties to the conflict to build a more peaceable future. The cardinal qualities of peacekeepers, as against those engaged in fighting wars, are that they should use the minimum level of violence necessary to achieve their goals and that at some level they should be impartial in the disputes between the parties. Importantly, they are representatives of the international community, not of their own country’s government and their own national interests. That is why peacekeeping is conducted by multinational forces, and unilateral efforts by one state to conduct ‘peacekeeping’ are liable to be regarded with suspicion.