This chapter explores the development of Nordic socio-spatial theories on nation, nationalism, and national identities. We begin by providing an overview of the body of theoretical work on nation by Nordic scholars, with attention to key authors, their main theoretical positions, and methodological orientations. We intend to show how the research area emerged by the early 1990s as a minor theme in Nordic human geography, but then developed and intensified in the subsequent decades, along with the rise of the subfield of political geography in some Nordic countries and Finland in particular. We also describe how the research field transformed in the 2000s, along with the growing interest in globalization and transnationalization. After this we move into reflections on nation and nationalism arising from our own research trajectories, and how they link with and build on the Nordic theoretical traditions. This discussion will situate our chapter both through our own work as Nordic scholars, and through empirical illustrations from Finland and Norway. We conclude by outlining current challenges and new horizons in Nordic theoretical work on nation and nationalism.