The Course will analyze the historical passage between the collapse of multinational Empires and the creation of Nation-States, focusing on one the main problems that this process created at the turn between the nineteenth and twentieth centuries, namely the conditions of national, ethnic and religious minorities. These dynamics coincided with the rise of internationalism and the construction of a new international settlement, which was based on the principle of national self-determination and on the ambitious project of consolidating peace through stable international institutions. In addition to the focus on different European cases (Balkans, Romania, Czechoslovakia, Poland, Russia) and on sepcific issues (antisemitism, refugees), the course focuses on the international mechanism that was created in order to guarantee minority protection and, though indirectly, peaceful relations among States in the context of the League of Nations. Some classes will be also devoted to theoretical aspects concerning the impact of nationalism and ethnicity, and to the influence that the interwar system of minority protection had for the successive construction of the United Nations, and for the conceptualization of ideas such as human rights and genocide.