Reviewed by: Canon Law, Religion, and Politics: Liber Amicorum Robert Somerville ed. by Uta-Renate Blumenthal, Anders Winroth, and Peter Landau Stanley Chodorow Canon Law, Religion, and Politics: Liber Amicorum Robert Somerville. Edited by Uta-Renate Blumenthal, Anders Winroth, and Peter Landau. (Washington, DC: The Catholic University of America Press. 2012. Pp. xix, 320. $69.95. ISBN 978-0-8132-1975-2.) Robert Somerville has spent his career tracing the gossamer threads connecting the surviving sources of medieval canon law, especially in the transmission of conciliar decrees. The work is delicate and often tentative, but Somerville has tried to give us some confidence in our knowledge. Many of those who have contributed essays to this volume honoring Somerville have used the occasion to take up shards of the medieval legal tradition and try their hand at what might be called the Somerville project. The book is a very fitting tribute to Somerville’s style and practice. [End Page 356] Somerville’s work has focused on the late-eleventh and early-twelfth centuries when the Church asserted and ultimately established its independent role in the politics of Europe. Conciliar legislation continued to regulate the life of the Church, but from this point on it also played a major role in the growth of secular institutions and in the political arena. The book is divided into three sections—Canon Law, Religion, and Politics—corresponding to the book’s title. The first section, “Canon Law,” consists of nine essays. With two exceptions, all of these pieces deal with the period that has been the focus of Somerville’s research. Bruce Brasington summarizes and edits a summula on excommunication and anathema from early in the second half of the twelfth century, and Peter Landau argues the case that the famous Ulpianus de edendo originated in Durham in the 1150s and was the first ordo iusticiarius in what became a library of such works. However, what distinguish nearly all of these essays are the knotty problems of transmission, dating, and geographical origin of the works tackled by the authors and their cautious, tentative conclusions. These are true essays, probing and testing the arguments for claims, and providing unfinished building blocks for a history of law. They will be of great value to those studying the history of particular works or traditions but not to those who seek sound foundations for works on general subjects. The second section, “Religion,” consists of two essays on theological works, Charles Shrader on the Eucharistic treatises of Heriger of Lobbes (c. 940–1007) and Martin Brett on the De corpore et sanguine Domini of Ernulf of Canterbury (1039/40–1124). Brett’s article includes an edition of the text. In the editors’ view, theology and canon law were separate subjects, although, as James Brundage notes in his essay in the third section of the book (p. 277), until the late-twelfth century practitioners did not regard canon law and theology as distinct fields of study. Nearly all of the essays in the third section, “Politics,” are by Somerville’s contemporaries—Detlev Jasper, Edward Peters, Giles Constable, Kenneth Pennington, Charles Donahue Jr., and James Brundage. Their essays tend to be more definitive than those in the earlier sections, in the sense that the authors draw conclusions from their research. Yet, several emulate Somerville in taking on topics about which conclusions are elusive. Jasper’s study of the transmission of historical examples of deposition and excommunication of emperors collected by papal partisans during the Investiture Conflict draws the tentative conclusion that a manuscript of St. Gall (Stiftsbibliothek 676) contains a version derived from two earlier lists, and Jasper edits the text from that manuscript. Pennington takes up a question raised by Somerville about a decree of the Second Lateran Council that prohibited monks and canons regular to study Roman law. He answers some, but not all, of the questions posed by Somerville in that study. Constable also deals with a subject close to Somerville: the evidence for Pope Urban II’s preaching of the first crusade. Most of the essays in the third section are contributions related to their authors’ longtime research and are useful additions to the puzzle of medieval legal...