The twentieth century saw the victory of the nation-state over all other forms of political organization. Empires and city-states have almost receded into history. Today, the principle of national sovereignty serves as the fundamental guide of international relations. The ideology of nationalism has reached all parts of the globe, and it is seen as natural that the world should be divided into nationstates, with each nation controlling its own state – however impossible that ideal might be to achieve. This is an ‘age of nationalism’ (Gellner 1983). However, over the past forty years there have also been signs that this world order might be changing. While states are still the most important actors on the world stage, the pressures of globalization and international trade have reduced their capacities to control their environments. In Europe, the European Union has gradually extended its own authority, taking over many of the competencies that were traditionally the responsibilities of its member states. As the political authority of states has been gradually dispersed to international organs, their internal homogeneity has also come under pressure. Subnational actors, such as regions, have begun to assert themselves on the international stage, with potentially severe ramifications for the economic and cultural coherence of the state. Growing spatial inequalities within states based on the success of some regions in attracting capital in the global market put pressures on national solidarity and give regions an incentive to mobilize in protection of their own interests (Bullmann 1997: 9). The effect of these historical developments has been to disperse political authority between the various layers of government to an extent not seen in Europe in the past seven centuries (Marks 1997: 20). As a result of these developments, political scientists have become increasingly preoccupied over the past twenty years with the topics of regions and regionalism. Whereas political science, and especially the comparative politics sub-discipline, used to focus mainly on states and nations, there is today a considerable body of literature on regions, cities and other sub-state levels of government. Much of this literature concerns regionalization within the context of the European Union (EU), focusing on new institutional phenomena such as regional information offices, the Committee of the Regions, multilevel governance and the ‘Europe of the regions’ agenda. It is the developments towards

regionalization and its consequences for nation-states and for the EU that have been at the centre of interest, while inquiries into the causes of regionalism have received comparatively less attention. However, there is significant variation in the mobilization of regions across different parts of the continent. Regions have long held substantial autonomy in federal countries such as Germany and Austria, and the German regions have consequently also acquired a substantial role within the political system of the EU. In Belgium, Spain and parts of the United Kingdom, they have become increasingly important, gaining authority over a wide range of policy areas. However, large parts of Western Europe have held on to unitary state structures, including the Scandinavian countries, the Netherlands, Ireland, Portugal and Greece, or have regionalized power only to a limited extent, such as France. Even within states, there are substantial differences in the degree to which the populations of different regions identify with their regions, and hence in the extent to which they mobilize on a regional basis. What causes such differences between regions in their capacity to mobilize local populations? Equally, if regionalism has been growing in many parts of Europe over the past few decades, what causes the levels of regionalism to vary across time within individual regions? These are the main questions addressed in this book.