This article examines history mediation and the relationship between education and academia. The aim is to investigate historical representations of the Christianisation in Sweden from 1915 to 1996, by doing a comparative analysis of the content in research publications and history textbooks for upper secondary school (or the equivalent). The research field and the textbooks are perceived as two different knowledge arenas. The analysis shows how the two arenas are more harmonious and consistent in their representations of Christianisation during the early twentieth century. In the mid-twentieth century, the arenas deviated from each other for an extended period, before finally becoming more unitary again by the end of the century. The impact of the schools’ steering documents, as well as the distinctiveness of the two arenas, seems to constitute the conditions for inconsistencies between them at different times. The analysis also suggests that the educational applicability of the knowledge content in contemporary research, likewise impacts the relationship between the two arenas.