This study analyzes the causes of civil wars in the Congo since independence and investigates how the Congo case fits the model of civil war proposed by Collier and Hoeffler. Five conclusions arise from this case study. First, the level and growth rate of national income increased the risk of war by reducing the cost of organizing rebellions and the government’s ability to counteract the rebellions. Second, while regional ethnic dominance served as a basis for mobilization of rebellions, ethnic antagonism was also an obstacle to the expansion of civil wars beyond the province of origin. Third, while natural resource dependence was a significant determinant of civil wars in the DRC, it is the geographic concentration of natural resources and their unequal distribution that made the Congo particularly prone to civil war. Fourth, the government’s ability to counteract rebellions depended more on external support than on the government’s military and economic capacity. Fifth, discriminatory nationality laws, disruptions in the ethnic balance of the eastern region caused by the influx of Rwandan Hutu refugees in 1994, and shared ethnicity between rebels and neighboring regimes—variables which are not included in the Collier-Hoeffler model—were significant determinants of the outbreak of civil wars in the 1990s.