What are the conditions in which some countries experience ethnic protests, while others do not? What are the conditions in which an ethnic community member will protest? What explains why some ethnic community members initiate an ethnic protest and some join later? Ethnicity is a crucial societal cleavage and ethnic protest a critical subtype of protest. It is not gender or class that challenge the territorial sovereignty of states, but ethnic-based opposition groups, often in the form of self-determination movements, that make the most extreme demands in terms of separatist policies. This dissertation adjudicates between conflicting expectations in the literature for why ethnic community members protest and why countries experience ethnic protest. It argues that an ethnic member’s decision to join an ethnic protest is affected by whether the ethnic member identifies primarily with the ethnic group, or with the ethnic group and the national group (dual identity) as well as if the ethnic member resides in a democracy or non-democracy. An ethnic member’s likelihood of ethnic protest participation impacts a country’s likelihood of ethnic protest. A multimethod approach tests the theoretical expectations. Survey-experiments amongst Afro-Panamanians in Panama (which is a democracy), and Greek Orthodox in Lebanon (which is less democratic) examine the micro-level expectations. Interviews with Syrian refugees in Lebanon and with Syrians in Syria via Skype complement the survey-experimental work. The micro-level analysis finds that in non-democracies, dual identity is associated with a decrease in ethnic protest participation likelihood. The decrease is greater during later stages of an ethnic protest. In democracies, however, higher levels of dual identity do not associate with a decrease in ethnic protest participation likelihood. Event data and Afrobarometer survey data are used to examine the conditions in which countries experience ethnic protest. Consistent with the micro-level analysis, in non-democracies, dual identity is associated with a decrease in ethnic protest likelihood. The dissertation finds a previously unexplored conditional effect of identity. In non-democracies, even with a simultaneous ethnic identity, maintaining a national identity can decrease intent to protest.