The aim of this thesis is to observe and analyze the effects of religious dimensions in armed conflict on violence against civilians. Focusing on rebel groups in intra-state conflicts, quantitative statistical analysis in form of Ordinary Least Squares multivariate regression, is utilized to examine data onreligious wars, one-sided violence, and conflict-related sexual violence. Two hypotheses are formulatedand tested; that (1) higher significance of religion in armed conflict leads to higher levels of one-sidedviolence, as well as that (2) higher significance of religion leads to higher levels of conflict-related sexual violence. The results, relying on four different datasets and 1107 observations, empirically support both hypotheses. The conclusion of this thesis suggests that civilians are found to be particularly vulnerable in religious armed conflict, pointing to the importance and urgency of further and closer examination of civilian victimization in these types of wars.