Using the developments in key multinational states, including the United Kingdom, Spain, Belgium, and the United States, this book explores both the impact of the pandemic on nationalism and the broader multinational state as well as the significance of multinationalism for the response to the pandemic. Exogenous forces have the potential to significantly impact the shape and dynamics of multinational democracies. The Covid-19 pandemic is one such powerful exogenous force. The chapters in this edited volume, therefore, investigate the following questions: (1) How has multinationalism shaped the response to the crisis? (2) How has the crisis affected the self-determination objectives and strategies of the nationalist movement? (3) Have national divides (as observed, for example, in public opinion and in statements from politicians) become more or less salient during, and as a result of, the crisis? (4) What issues have produced tensions between national communities, or between minority nations and the state? (5) What governments, parties, or individual politicians have most gained or lost from the crisis in terms of putting forward or managing self-determination claims? (6) What could be the impact of the crisis on the nationalist movement and on the multinational state as a whole? The book will be essential reading for academics, researchers, and policy-makers of political science interested in the fields of federal theory, multinationalism, minorities and natural disasters. This book was originally published as a special issue of Nationalism and Ethnic Politics and is accompanied by a new concluding chapter.