In historical and comparative studies of civil wars in the Cold War era the agency and individual motivations of members of “proxy” groups sponsored by foreign powers are frequently overshadowed by the broader international political project of their patrons. However, fighters in these groups often have complex and varied reasons for group adhesion and taking up arms, reasons intimately tied to the local and national, rather than international, political and social context. In Mozambique, the Resistência Nacional Moçambicana (Renamo) was organized by the Rhodesian Central Intelligence Organisation and became known for committing atrocities and forcibly recruiting members during its nearly twenty year war against the new government led by the Frente de Libertação de Moçambique (Frelimo). However, despite engaging in indiscriminate violence, Renamo received many volunteers throughout the war and developed a social base that has endured through the group’s post-war transition from insurgent group to opposition political party. Integrating the political science literature on the structure and program of Renamo with anthropological accounts of the group’s appeal to certain sectors of Mozambican society, this paper uses the case of Renamo to examine how proxy groups can generate domestic support and develop into social movements in their own right.