How do rural communities respond to threats of insurgent violence during civil wars? In certain conflicts, insurgents employ indiscriminate violence against rural communities (Downes 2006; Humphreys & Weinstein 2006; Metelits 2010; Mkandawire 2002). In response to such violence, some communities create armed self-defense groups. By an armed self-defense group, I mean an armed group that is set up by community members on a voluntary basis to provide protection to their community against insurgent violence. The formation of armed self-defense groups is not uncommon in civil wars. Examples of conflicts in which armed self-defense group emerged include the civil wars in Algeria (Martinez 2000, p. 151), Peru (Kay 2001, pp. 751-752; Degregori 1999; Starn 1995), Sierra Leone (Hoffman 2007, p. 647) and Sudan (Young 2003, p 430). Within these wars, formation of armed self-defense groups has been uneven: some communities formed armed self-defense groups and others did not. In this project, I will investigate variation in the formation of armed self-defense groups within civil wars. I will conduct a comparative analysis of four communities located in the same province in South Sudan. During the civil war in South Sudan (1983-2005) all four communities experienced insurgent threats and low levels of government protection. Yet only two of the four communities decided to create armed self-defense groups.