How Does Relative Group Size Affect Civil War Risk?

The literature on social polarization predicts that redistributive conflicts will be most intense in societies with two equally large groups. However, the effect of relative group size on the risk of onset of violent conflict remains unexplored. In this paper we study a game between a rentextracting government and an excluded social group which can explain the determinants of conflict onset and help to interpret the empirical civil war literature. Although the model is too complex to solve analytically the simulation results show that (1) the risk of conflict onset is maximized with two equally large groups, but (2) the onset risk in any given year depends on which group controls the government. (3) The relative size of excluded majority groups, their ability to overcome collective action problems, patience levels as measured by the discount factor, and natural resource rents can all have a non-linear effect on the risk of conflict onset.