Niels Hemmingsen (1513-1600) is one of the most influential Danish theologians in history. As a professor at the University of Copenhagen, Hemmingsen played an important role in moulding Danish society according to his understanding of Lutheranism during the second half of the sixteenth century. Drawing on sociology of knowledge, cultural memory, and confessional culture, Mattias Skat Sommer examines Hemmingsen's works and life in political and theological contexts. By studying Hemmingsen's role in forming a discourse of social interaction, the author argues that Hemmingsen was the leading agent in shaping post-Reformation Danish confessionalization. In doing so, Sommer emphasises the fluid boundaries of the Danish Reformation and adjusts two prominent theoretical frameworks discussed in contemporary research on early modern Europe, namely those of confessionalization and confessional culture.