This dissertation outlines continuity and change in Swedish radical nationalism – a political ideology predominantly focused on connecting an imagined people with a distinct territory. The study focuses on how religion has been understood within the landscape of Swedish radical nationalism between 1988 and 2020. The landscape is termed radical-nationalist since its central articulation is nationalism. It is radical because of its actors’ urge to return nationalism to its roots, without compromising with other political ideologies, and because it is seen as a radical solution to the problems of national degeneration. The Swedish radical-nationalist landscape consists of ideological formations that are culture-oriented, race-oriented, and identity-oriented. These formations animate the actors moving across the landscape. Three such actors are analyzed in the dissertation, each having its own history and distinct position in relation to the ideological formations: the political party Sweden Democrats, the national socialist organization Nordic Resistance Movement, and the online influencer The Golden One. The study builds on a theoretical shift, usually labeled critical religion theory, which departs from religion as an analytical category to instead focus on the various definitions of, and ideas about, religion among the actors themselves. Religion is analyzed as a political concept within Swedish radical nationalism. The terminology of political concepts is borrowed from the theory of ideological morphology, where such concepts are located on an axis between center and periphery of a political ideology, from core concepts via adjacent concepts to peripheral concepts. In Swedish radical nationalism, the concept of religion is a demarcation against them, external enemies as well as internal traitors. Religion functions as an essential exclusionary mechanism aimed at imagined Others who are assumed to, in varying degrees, be superstitious, conspiratorial, fanatical, or divisive. However, the concept of religion also construes us, an imagined people, through ideas of a shared collective unconscious and a Volksgeist that via paganism and Christianity travels from a distant, and often forgotten, past. In conclusion, religion is recurrently one of the adjacent concepts that temporarily stabilizes the core of Swedish radical nationalism: people and territory. Like other concepts that are adjacent to the core – such as culture, race, and identity – the concept of religion stipulates who belongs to the people and the territory, and who should be excluded, disadvantaged, or eliminated.