Book Review: The Gregorian Calendar Reform: Die Gregorianische Kalenderreform von 1582: Korrektur der christlichen Zeitrechnung in der Frühen Neuzeit

Abstract

THE GREGORIAN CALENDAR REFORM Die Gregorianische Kalenderreform von 1582: Korrektur der christlichen Zeitrechnung in der Fruhen Neuzeit. Dirk Steinmetz (Verlag Dirk Steinmetz, Offersheim, 2011). Pp. 502. euro65. ISBN 978-3-943051-00-1.Since the seminal studies of Schmid and especially Kaltenbrunner towards the end of the nineteenth century, the Gregorian calendar reform has generally received little attention. A noteworthy exception is the proceedings of the Vatican conference commemorating the 400th anniversary of the event in 1982, which, however, is not widely available. This lack of interest is the more surprising, since the calendar reform had serious cultural, political, religious, and social implications, many of which remain to be thoroughly investigated.Dirk Steinmetz's monumental Heidelberg Ph.D. dissertation is therefore a very welcome publication, one that will hopefully stimulate renewed interest in what must be considered as one of the most important cultural events of the early modern period. It seeks to survey the Gregorian calendar reform, covering its mathematicalastronomical, political, theological, and cultural aspects. It starts with a brief outline of the history of the calendar before the reform and a basic description of its most relevant features (pp. 22-71). It then discusses all texts relevant to the reform proper and its immediate reception in Europe (pp. 72-360), Protestant struggles to come to terms with it and their attempts to provide alternatives up to the nineteenth century (pp 361-414), as well as later attempts at reform (pp. 415-24). At the end, we find a glossary (pp. 427-33), miscellaneous tabular materials (pp. 434-59), a computer program for calculating Easter (pp. 459-65), a list of territories and the dates of their introduction of the Gregorian calendar (pp. 466-70), a graphical illustration of the relation between selected texts (pp. 470-1), and finally common lists of illustrations, abbreviations, and bibliography (pp. 472-502). There are no indices.The foreword states that this handsome production is written for the novice as well as the scholar. However, novices not trained in other languages may find it difficult to follow the argument, as the extensively cited sources appear only in the original, primarily Latin and Italian. Also, why provide a computer program in outdated Turbo Pascal, when excellent calculators and converters of Easter dates and calendrical features are readily available on the web (e.g., the extremely useful www.nabkal.de)? References to such online tools surely would have been more welcomed by novices.For the scholar, the strongest part of the book is the core, dealing with the Gregorian calendar reform proper and the immediate reactions caused by it. Here, Steinmetz presents a wealth of material, conveniently Usted in two excellent tables (pp. 99-105, 348-60). Most noteworthy is his identification of previously unknown copies of the Compendium novae rationis restituendi Kalendarium, one of which (Rome, Biblioteca Nazionale Centrale, 71.2.D.35) is Clavius's own copy. The general perspective on this material is principally that of the historian of science, although some interesting cultural aspects such as logistical problems of introducing the reform in Spain (pp. 133-8) are noted. In the end, Steinmetz only scratches the surface of the many fascinating aspects of the Gregorian calendar reform, its preparation and implementation, and it can only be hoped, as the author stresses himself (p. 15), that cultural, social, political, ecclesiastical, and intellectual historians will dig deeper.Beyond this core period, Steinmetz is less at home, due principally to his tendency not to consult the original sources and to rely on outdated general literature. Thus, certain important sources and details are overlooked, others are described misleadingly or are simply wrong. A few examples may serve to illustrate this, as we turn first to the reception of the Gregorian calendar and other attempts of reform triggered by it. …