Ulrich A. Wien, academic director at the Institute of Evangelical Theology at Koblenz-Landau University and a longstanding researcher of early-modern Reformation, has published earlier this year a collection of essays—either original or previously printed in German in various publications—under the umbrella concept of “theological diversity”: the Transylvanian “intra-Christian religious discussions,” as the author defines them, are examined and dissected against the backdrop of the sanctioned freedom of proclamation and the Ottoman suzerainty over the province. The 15 chapters of the volume analyze in the course of 350 pages the two-century-long confessional struggles of the so-called Transylvanian Saxon community and the extension of their recollection into the twentieth century.The introductory chapter (pp. 15–52) synthesizes the historiographical state-of-the-art concerning the evolution of the East European province of Transylvania within the administrative frame of the Kingdom of Hungary, the mid-eleventh-century settlement of Western colonists and their evolution towards political, administrative, and ecclesiastical unity in the fifteenth century, rounding off the chapter with the reception of the Wittenberg Reformation in the 1570s and the effects of the 1595 Diet, which conferred legality to Roman Catholics as well as to other confessional groups emerging from the confessional change: the Lutherans, Calvinists, and Unitarians (“Arians”).An ambitious heading inaugurates the proper topic announced by the volume’s title: “Pioneer Region of Religious Freedom—Reception and Negotiation Process of the Transylvanian Reformers in the 16th Century” (pp. 53–66). The chapter discusses the response of Transylvania’s ethnic groups, the Orthodox Romanians and Catholic Hungarians, and Saxons, to the ideas developed by the German and Swiss revisionists of Catholic theology. The Transylvanian advocates of the Protestant Reformation make for ideal case studies in the next four chapters: “The Humanist Johannes Honterus—publishing activities, theological orientation and intellectual networks” (pp. 67–84), “The Hymnal (1543) of Andreas Moldner—Spiritual Openness and Ethical Emphasis in the Urban Reformation of Kronstadt (Transylvania)” (pp. 85–104), “Reconciliation in a Village Community in the Reformation Period in Transylvania—Preliminary Remark” (pp. 105–116; discussing the biography of Damasus Dürr), and “Supervision of ‘Governing Authorities’ and ‘Community’ by the Church as a Guardian of Order—The Positioning of Damasus Dürr between Assertion and Reality” (pp. 117–136). Every analysis is placed in context, considering the previous research on the topic, and drawing on original, unpublished documentary sources.The following chapters, each expanding a particularity of the Transylvanian confessional landscape, point out to the reader the complex entanglement between actors and theological doctrines: “No Place for the Doctrine of Justification in the ‘Ecclesia Teutonicorum’ in Transylvania?” (pp. 137–148), “A Departure from Trinitarian Theology?—Concerning the Complexity of the Disputations and Religious Colloquia in Transylvania” (pp. 149–188), “A New Perspective on the Formation of Confessions in Early Modern Transylvania—The Context and Theological Profile of the Formula Pii Consensus 1572 as a Heterodox Reception of the Wittenberg Theology” (pp. 189–206), “Flight behind the ‘Ottoman Curtain.’ Religious Refugees in Transylvania” (pp. 207–226), “Effects of Calvinism in Transylvania in the 16th and 17th Centuries” (pp. 227–256), “The Reformed in Transylvania as Seen by the Evangelical Transylvanian-Saxons” (pp. 257–272), “Politics – Power – Faith. Controversies, Conflicts and Efforts toward Consensus in Transylvania between Landeskirche and Nationsuniversität from the Mid-1500s until the Mid-1700s” (pp. 273–286), and “The Synod of the Evangelical Superintendency in Birthälm and their Records of Negotiation (1601–1752)” (pp. 287–310). These sections detail the negotiation stages—discussion, disputation, conflict, antipathy, and acceptance—leading to the transfer of Central European theological interpretations and up to the development of the Protestant spectrum in sixteenth-century Transylvania. Similarly, the heterogenous political (the Ottoman and Habsburg Empires), institutional (the Saxon University, the Transylvanian confessional churches), and social (theologians, refugees, nobility) actors are portrayed from the perspective of their interaction with the Evangelical Transylvanian Saxons. The group’s inner transformations, in terms of educational support or social discipline of the clergy and parishioners, confer a deeper dimension to the confessional change.A concluding chapter entitled “‘What? Your Honterites, are they already asleep?’ Memoria of the Transylvanian-Saxon Reformation from the 17th through the 20th Centuries” (pp. 311–332) brings the topic beyond the temporal limits or early modernity up to the 500th anniversary of the birth of Martin Luther in 1983. These celebrations highlight the particular profile of the Transylvanian Saxon’s Evangelical Church as a “folk church,” whose striking characteristic was the superposition of a German-speaking ethnic group and a confessional congregation.A few observations—that are, however, only superficial quirks of a volume which is generally judiciously constructed—must be brought forth. The opening chapter dealing with the history of the Transylvanian Saxons’ community until the late 1500s develops as a synthesis of previously published material (with only a few very recent contributions), recycling some historical narratives developed in the nationalistic-driven historiographic context of the twentieth century: the so-called “empty” spaces that needed populating by an ethnic group with superior technical skills, the class-divided society in conflict with each other, and the thirteenth-century settlement of nomadic Wallachians are elements of what is perceived today as an obsolete quasi-colonialist discourse. This is, unfortunately, the result of a long-overdue update of methodological approaches in what concerns the early formation of Transylvania’s institutional, social, and cultural landscape. Additionally, this chapter requires an editorial review, meant to mend those inconsistencies in citing authors and papers (footnotes 3 and 6 quote the same author and paper in two district ways; same with footnotes 29, pp. 24 and 34, p. 26), as well as some incorrect name references (for instance, “SCHABEL” is the accurate spelling, instead of “SCHNABEL” on p. 22, footnote 21, and p. 342). Other minor observations concern the use of “Theology and Spirituality” as both the name of a chapter and a sub-chapter, and the erroneous title “The Celebration of the 500th Birthday of Johannes Honterus” on page 326 with reference to the celebration of the Lutheran reformer’s 400th birthday in 1898. All in all, this volume is a welcome and insightful revaluation of the impact of Reformation in Transylvania, promising to become a useful tool for any historian, enthusiast to professional, looking to expand their research interests.