Throughout the twentieth century, glaciologists and geophysicists in Norway and Sweden, as well as Danish geoscientists and ice core scientists in Greenland, made important contributions to polar field science. It is in the polar regions, especially in the Arctic, where Norden has a strong presence and a geopolitical significance that punches far above its weight in terms of population, geographical size, or economic activity. This volume explores the critical issues related to the significance of an 'Arctic Norden'. Empirically the contributors focus on science relations between Sweden and Norway in the twentieth century and their contributions to policy and diplomacy, particularly in the International Polar Years, but the perspective in the book includes a wider North Atlantic realm.