Christine Helmer’s book How Luther Became the Reformer is not a typical history of Martin Luther. At its core, the book is an examination of historical interpretations of Luther.
 Helmer is a professor of the Humanities and German at Northwestern University. Her areas of study include Martin Luther, Friedrich Schleiermacher, and the Luther Renaissance, and you do see these areas of interest come together in this book.
 Her fundamental question, as implied by the title of the book, is how did Luther become the Reformer. She states that John Calvin has had a much larger impact on a global scale, but it is Luther who “appears in the public imagination as the instigator of modernity” (3). And it is this interpretation of Luther—Luther as a critical point in the establishment of Western modernity—that occupies much of her attention. She tries to answer her question primarily by examining Luther scholars from the German academy at the beginning of the twentieth century, known as the Luther Renaissance, who she argues have had a profound influence on how Luther has been and continues to be understood.
 Helmer argues that alongside the myth of Luther as the one to usher in modernity, Catholics and Jews have been cast as antithetical to modernity and viewed as “other.” She states that the “book ultimately aims at constructing a Luther from a historically responsible perspective who can take us a step further in thinking through urgent questions today” (13). To do this, one needs to view Luther in his late medieval Catholic context.
 Helmer’s argument that Luther should be viewed in his Catholic medieval context is, in my opinion, correct. I would have liked some more theological underpinning to this argument, but the reasoning behind this assertion is solid. Luther operated within a late medieval European framework; he was educated by medieval Catholic scholars, and he was a Catholic monk. She goes a step further though, and in Helmer’s last chapter, she argues for an interpretation of Luther as a Catholic reformer (lower case r reformer, as opposed to the Reformer). There is validity to this argument, and it is largely accepted that in 1517 Martin Luther was not looking to break from the Catholic Church. However, eventually Luther did. Luther rejected fundamental aspects of the Catholic faith, not to mention his polemic against the Catholic Church, so I do question whether he can truly be seen as a Catholic reformer (though he has admittedly influenced Catholicism in profound ways).
 While Helmer poses that she wants to situate Luther in his late medieval context, she does surprisingly little to advance this interpretation. She relies again on a history of interpretation, and demonstrates that there has been an increase in ecumenical cooperation and interpretation especially following Vatican II, but the book would have benefitted from more examples of how Luther’s theology and actions fit more within a medieval framework rather than a modern one.
 Likely the most important and interesting chapter of the book is chapter 5 entitled: “A Test Case for Anti-Judaism.” She tackles head on Luther’s anti-Jewish texts within Luther’s larger historical context. She argues that too often scholars have tried to excuse Luther’s violent polemic against the Jews by arguing that he was old, sick, disillusioned with the Reformation, or even that he was simply a man of his time. While his most egregious anti-Jewish writings are from the latter part of his life, she argues that there are aspects of anti-Judaism that run through Luther’s works. She traces this anti-Judaism to modern anti-Semitism, the rise of Nazism, and the Shoah. This chapter alone makes the book worth reading.
 How Luther Became the Reformer is a slim volume—a mere 124 pages—but it is dense. A basic understanding of Luther’s biography and theology would likely be necessary for readers approaching this book. Helmer does occasionally give some broad historical overview, but overwhelmingly this is a book that assumes a great deal of knowledge about Luther, his theology, and his context.
 Helmer frames the book by referencing contemporary issues that the world is facing, however, one possible weakness is her brief attention to current events. And since the book was published in 2019, this section already feels dated since the Covid-19 pandemic has fundamentally changed so much.
 One final point about Helmer’s work is its contribution to the history of interpretation. History tells us of both the past and the present. As a historian, I appreciated her examination of how different historical time periods have influenced Luther scholarship. It is a good reminder to us that we are always influenced by own contexts though we may be unable to see it ourselves. While it makes sense that she focuses so heavily on German interpretation, it would have been interesting had she included a more robust examination of other schools of interpretation.
 This book is not going to appeal to everyone. It is dense enough that it feels rather “academic,” and there is a level of assumed knowledge for the reader. That being said, I enjoyed the book. I found her deep dive into the Luther Renaissance to be interesting; I appreciated the space she devoted to Luther’s anti-Jewish writings; and I thought her argument for a Luther interpretation that was more connected to his late medieval Catholic milieu to be convincing. As a historian, I also appreciate her analysis of historical interpretations of Luther’s legacy. I think Helmer brings a worthwhile perspective and an interesting addition to Luther scholarship.