This dissertation explores the how external threat from militarized interstate disputes and interstate rivalries affect the relationship between the state and the ethnic groups within its borders. Specifically, it finds that national identity, the preservation of ethnic regional autonomy, and the formation of ethnic-based militias are all influenced by states involvement in international conflicts. In Sub Saharan Africa, discriminated groups are less likely to identify with their national identity and when the state is involved in an interstate dispute, while the rest of the country increases their likelihood to identify with the nation, discriminated groups cling to their ethnic identity. During and interstate rivalry, ethnic groups face a heightened risk of the state taking away their autonomy over a region. If the rivalry becomes too intense or the ethnic group shares kin with the rival, the ethnic group has lower chance of losing their autonomy during rivalry. Finally, ethnic minority seeking to form a militia are able to form one faster if their ethnic group is well represented in the military's rank and file or if their co-ethnics in the rank and file had combat experience in an interstate dispute were military force was used. Ethnic groups that are well represented in officer corps are less likely to have organizations with militias especially if those officers have combat experience. Using a logistic regression and Cox proportional hazard models I find a strong link between interstate conflict and ethnic politics.