This introductory article opens the thematic issue Spaces of Upset in the Nordic Region. It introduces the contributions of the issue, outlines the concepts that unite them, and discusses the sociolinguistic area in which they are set: the Nordic region. Centering on Denmark, Finland and Sweden, the article offers an overview of some of the sociolinguistic, ideological and political characteristics of the region and the countries it comprises. The Nordic region is widely seen as a paradigm case of social stability, consensus and cohesion. This vision is, however, a mirage. To be sure, upset often lingers below the discursive veneer of Nordic harmony, concord and agreement. Breaking with this outlook, this thematic issue takes a closer look at some of the antipodes of this sociolinguistic and ideological condition. Its contributions engage with ‘spaces of upset’, that is, with manifestations and experiences of sociolinguistic rupture, upheaval or change, in and through which visions of sociolinguistic stability and cohesion are disrupted and challenged. These spaces of upset bear witness to social, ideological and linguistic tensions and changes, be they incipient, enduring or surpassed. They accordingly provide a new take on processes of continuity and change, pointing out the ideological faultlines of the orders they disrupt, or upset.