Reviewed by: Reformation und kalkulierte Medialität by Hannah M. Kress Martin Berntson Reformation und kalkulierte Medialität. By Hannah M. Kress. Beiträge zur historischen Theologie 200. Tübingen: Mohr Siebeck. 2021. 475 pp. Hannah M. Kress has written a doctoral thesis, defended at the University of Marburg, on Olaus Petri, the foremost theologian in [End Page 238] Sweden during the early Reformation. Through a medial perspective, the author treats Olaus Petri's texts in a new way, with a focus on the Reformation as a communication process, where the transmission of knowledge concerns messages that take concrete and practical expression. Kress hereby seeks to determine how the printing medium was used in a calculated way to spread the Reformation during its earliest phase in Sweden. By analyzing title pages, images, and printing fonts, she makes inferences and through the marginal notes she gets a glimpse of how the books were received. Wisely, however, Kress does not only study the books, but places them in the larger political context, investigating how they were both influenced by and supported royal policy. The book is very carefully structured. Each writing attributed to Olaus Petri (sometimes he was not the actual author, sometimes he can only be considered a translator) is examined with a focus on structure and content, as well as possible original sources and graphics. Among the most interesting analyses is that of the books' title pages. In the sixteenth century, Olaus Petri's books were divided into three series (two in quarto format and one in octavo format). One series focused on classical Reformation topoi, and another more in-depth on classical theological topics, while the octavo format series was focused on personal edification. The format and cover allowed the reader (or buyer) to see immediately what kind of book it was. Kress continually addresses the question of whether it is appropriate to speak of a magisterial reformation (Königsreformation) in Sweden. Kress argues that the oft-recurring—but in my opinion not the predominant—view of the Swedish Reformation as solely a magisterial reformation is reductive, especially when it comes to the introduction of the Reformation in the kingdom during the mid-1520s and mid-1530s, where one should instead be open to a more differentiated interpretation. Based on previous definitions of a magisterial reformation, especially by Wilhelm-Ernst Winterhager and Eike Wolgast, Kress argues that the introduction of the Reformation in the Swedish kingdom cannot generally be described as such, but rather was a matter of both idealistic and material forces working together. [End Page 239] At times, it would have been desirable for the author to refer more often to literature written after 1945. It is, for example, questionable to label a handbook by Professor Hjalmar Holmquist from 1933 as a prevalent standard work for Swedish Reformation history (3). Through the use of older literature, the author transmits the view that the spread of late medieval relic veneration, Marian veneration, pilgrimages, and the trade in indulgences were due to poorly educated Swedish priests, as well as to the fact that the practices took non-Christian or pagan forms. These dubious statements also include the claim that belief in the pagan gods Thor and Odin would have been "widespread" at the time of the Reformation and that the population outside Stockholm was largely not even Christian (38). The occasional limited connection to recent research is, however, richly compensated by the author's skill in working both close to the sources and in a source-critical way. The often very detailed summaries of the contents of Olaus Petri's books would perhaps have been superfluous if the book had been written in Swedish, but as it is primarily aimed at a German readership, her summaries will serve as an excellent introduction to someone who is completely unknown to most English- and German-speaking Reformation scholars, namely, the versatile theologian Olaus Petri. Martin Berntson University of Gothenburg Gothenburg, Sweden Copyright © 2023 Johns Hopkins University Press and Lutheran Quarterly, Inc.