Bauer uses the case of Onofrio Panvinio (1530–1568), an Augustinian friar, to shed light on the development of history writing in early modern Rome as well as on the historiography of the papacy. Panvinio, who left few published works but many manuscripts at his death, accomplished a remarkable amount of historical research during his short life and, as Bauer demonstrates, was an important innovator in historical method. The book’s title refers to Bauer’s thesis that Panvinio’s ambitious collection of primary source material, together with his source criticism and willingness to ask hard questions about the nature of change in the Church’s past, amounted to the invention of modern papal history.The focus on Panvinio’s life also allows insight into the pressures and opportunities faced by historians of the sixteenth century in attempting to work on church history in general and papal history in particular. Indeed, ecclesiastical interest in history was so great at the time that Panvinio’s order was willing to release him from its normal constraints to travel broadly in search of historical materials and to devote his life to historical scholarship. Panvinio’s constant need to find wealthy and politically powerful patrons—for the most part within the Church hierarchy—offers further evidence of what was required to have the luxury of research and writing.Panvinio’s earlier work on ancient Rome was pioneering in its use of multiple sources and methods, from literary works and epigraphy to numismatics and archaeology. His later work largely focused on the history of the papacy and papal elections. After his first two chapters, which provide an intellectual biography of Panvinio, Bauer examines in detail Panvinio’s history of papal elections and the nature of censorship in Rome in the sixteenth and into the seventeenth century.According to Bauer, Panvinio was the first scholar to write a comprehensive account of the many changes in papal elections from their beginnings to his own day. Among the key innovations that he examined were the attempts to eliminate lay influence, including the decree in 1059 limiting electors to cardinals, the introduction in 1179 of the requirement of a two-thirds majority to elect a pope, and the introduction of the conclave, with its exclusion of the outside world, in 1274. Such was Panvinio’s ambition that while completing the ten (unpublished) volumes of this study, he wrote a history of imperial elections—the first one to offer a detailed study of the election of emperors from ancient Rome to the sixteenth century.As Bauer recounts, papal history was a minefield at the time, partly because of the competing papal family dynasties. When a particular family was in power, sympathetic biographies of its popes were much appreciated, but a change in papal regime could render those same biographies unwelcome. With the onset of the Counter-Reformation (or, in Bauer’s terminology, the Catholic Reformation), anything that shed a negative light on the papacy could become victim to censorship; by late in the sixteenth century, Panvinio’s works themselves fell victim to these efforts.In an epilogue, Bauer offers some thoughts about the development of ecclesiastical historiography in the decades and centuries after Panvinio’s death. Most notable was the general lack of interest in church history. Not until the mid-eighteenth century did the Jesuit Collegio Romano introduce its first chair in ecclesiastical history. As for papal biography, the modern form of which Panvinio had introduced in the sixteenth century, it had been reduced to a mere panegyric exercise in church propaganda by the following century. The Church recruited historians into the battle against Protestantism, expecting them to play their part uncritically.The sources that Bauer used for this book are impressive, encompassing a large number of both manuscripts and published works from the sixteenth and early seventeenth century gathered in ecclesiastical and civil archives and libraries in Italy, Spain, Denmark, Germany, Britain, France, and Vatican City. Although the subject may strike those outside the field as arcane, the book offers in compact form valuable insight into an important part of the evolution of European historiography. The book will be especially valuable to early modern European and Church historians, but is accessible to non-specialists as well.