Chapter 2 starts with an overview of the modern phenomena of ethnicity, nationalism, and ethno-national conflicts, and about the probable causes and background conditions that provide fertile ground for their outbreak, as these understandings are essential for evaluating the prevailing theoretical assumptions about justice and democracy in places of ethno-national conflict. To deepen the understanding of the sociology of ethno-national conflicts, the chapter introduces the four conflicts of Bosnia and Herzegovina, Northern Ireland, Cyprus, and Israel–Palestine. This chapter singles out political exclusion, the struggle over public goods of the nation-state, and group inequalities along ethno-national lines as leading factors that explain the outbreak of violent conflicts.