The importance of the city-state, as one of the principal forms of geopolitical organization in early modern Europe, culminated with the Hanseatic League of city-states located around the Baltic and the North Sea. The relationship of the League with other emerging types of state, particularly the nation-state, is examined, and the extent to which the nation-state was a cause of the city-state's decline is addressed. The author concludes with an examination of the role of the city-state in the contemporary world, focusing on its re-emergence in parts of the Far East and the Islamic world in the post-imperial era. In this context, he assesses the possible role of the city-state in the twenty-first century and beyond.