Personal and collective threat can breed ethnocentrism and intergroup conflict. We present a model of group-based control to elucidate motivational underpinnings of these effects from a social psychological perspective. Reviewed empirical evidence illustrates the effects of personal threat on ethnocentric attitudes. Moreover, evidence reveals that perceived lack of personal control of important aspects of one's life induces people to support and defend social in-groups. This is because people heuristically believe that groups are homogeneous actors of shared goals that may promise the symbolic restoration of group members’ sense of global control. We discuss the effects complex real-world threats (economic crises, terrorism, and climate change) have on ethnocentric tendencies and how we explain this within the control model. Finally, we elaborate on implications for reducing ethnocentric threat responses and on possible prosocial consequences of threat that may help to solve societal crises.