The objective of this article is twofold. Firstly, I seek to improve understanding of Swedish citizenship by highlighting the particular traits of an open yet largely instrumental (non-sentimental) membership policy, which existing theories have not been able to fully account for. I argue that the liberal openness of Swedish citizenship should be attributed not only to a liberal ideology of pluralism and equality, but to a fairly administrative, sterile and pragmatic conception of citizenship that is largely dissociated from existing conceptions of nationhood, integration and societal membership. Secondly, and related to the first, I take issue with the widespread yet implicit theoretical notion of citizenship being defined by shared conceptions of the national demos. I argue that this connection varies and that it is significantly closer and stronger in some cases than in others, regardless of its lenience towards an ethnic or civic, monist or pluralist conception of the nation. While newer, post-national theories of citizenship offer valuable insights into the reshaping of citizenship, they systematically underestimate and, consequently, fail to account for the enduring differences between and idiosyncrasies of national citizenship regimes. To better capture this neglected dimension of the citizenship-nationhood nexus, I propose a distinction between ideologically thin and thick citizenship, with Sweden serving as an example of the first.