Although past scholarship shows that group inequalities in economic and political power (“Horizontal Inequalities”) correlate with dissent, violence, and civil wars, there is no direct empirical test of the perceptual explanation for this relationship at the individual level. Such explanation is vital to understanding how integration, inclusion in power-sharing agreements, and exclusion from political power filter down to mass publics. Moreover, subjective perceptions of group conditions do not always correspond to objective group realities. We hypothesize subjective perceptions attenuate the effect of objective exclusion on support for violence in ethnically divided societies. Cross-national comparative multilevel analyses of the 2005/6 Afrobarometer dataset (N = 19,278) confirm that subjective perceptions both amplify the effect of exclusion on acceptance of violence and alter the readiness of included groups to dissent. These findings carry implications for research, state-building, and conflict management.