The monograph analyzes the evolution of interethnic relations in the Soviet Union in the last period of its existence from the standpoint of modern scientific knowledge. A description is given of the complex and contradictory process of growing interethnic contradictions and loss of interethnic trust in the country. The rich factual material shows the mechanism of the emergence and development of ethnic conflicts in the vastness of a huge state. The collapse of the USSR is presented as a result of the implementation by the ethnoelites of the program of political ethnonationalism in the national republics. For teachers, scientific experts and everyone interested in Russian history.