This thesis examines the role of ideology for political violence. It looks more specifically at the interaction of ideology and ethnicity - how and what type of ideologies of ethno-political organizations translate into mobilization and violence. The results suggest that the integration/disintegration characteristics of ideologies of ethno-political organizations is the main source for their choice of a violent strategy. While holding integrationist ideologies restrain organizations from using violence, having a territorial disintegrationist ideology or a normative disintegrationist ideology with rigid political and religious doctrines increases the likelihood of organizations using violence. Furthermore, these impacts depend on state institutions and regime type, and are conditioned by state behaviour. Repressive state behaviour and discrimination increase this probability especially in less democratic and authoritarian regimes. Overall, the results suggest that armed conflicts are not only driven by economic systems, but also by ideological struggles that must be considered for conflict resolution.