Reviewed by: Codex Epistolaris Carolinus: Letters from the Popes to the Frankish Rulers, 739–791 Sam Collins Codex Epistolaris Carolinus: Letters from the Popes to the Frankish Rulers, 739–791. Translation, introduction, and notes by Rosamond McKitterick, Dorine van Espelo, Richard Pollard, and Richard Price. (Liverpool: Liverpool University Press. 2021. Pp. xi, 546. £125. ISBN: 9781800348714). The tools for teaching the Carolingian age to new generations of students proliferate apace. Paul Dutton’s Carolingian sourcebook (2nd edition, 2004) stands at the head of this class, alongside the four royal biographies translated by Thomas Noble (2009), but these are but the start of the array of high-quality translations of [End Page 179] Carolingian sources now available. Given the range of Carolingian material available in recent translation, new students of this essential early medieval moment are positioned to study the period in a depth that was hardly imaginable even a few decades ago. To this formidable arsenal of accessible Carolingiana comes this very welcome and in all respects definitive translation of the Codex Epistolaris Carolinus, the latest it-eration in the series “Translated Texts for Historians” from Liverpool University Press. Between 739 and 791 a series of popes sent just shy of a hundred letters on matters great and small to the rulers of the Frankish kingdom, from Charles Martel to Charlemagne. Surviving in a single manuscript copy of the ninth century, the Codex Epistolaris Carolinus, as its contemporary preface tells us, stemmed from an initiative of Charlemagne to collect and preserve the letters sent to the rulers of his family by the Roman see. The subjects on offer in the letters are rich and varied and often right at the heart of key issues to the dynasty and papacy, both in a period of rapid and intertwined change and development. In the letters of the Codex Epistolaris Carolinus we are treated to glimpses of Carolingian mayors inching toward a coup against the Merovingians, negotiations over how to handle the shifting balance of power in Italy from Lombards to Franks, an armature of Old Testament ruler ideology in the making, canon law avant la lettre, and much more. Until now the letters have been best known to scholars through the problematic 1892 edition of Wilhelm Gundlach for the MGH. Of the editorial decisions that made that edition unsatisfactory was Gundlach’s adherence to a nineteenth-century instinct to rearrange the medieval order of the letters into a (purportedly) strict chronological sequence, as well as his banishing of the lemmata, the often-dis-cursive explanatory titles given to each letter by the Carolingian compilers of the text. To use the Gundlach edition is to encounter a Carolingian document with much of its Carolingian logic removed or hidden. All that is thankfully swept away here, and readers of this translation encounter the text as it appears in the manuscript and as its Carolingian compilers intended it to be read. This is the first complete English translation of the letters, and it is an important service to the field to make them so easily and accessibly available. Four introductory sections precede the translation. After a general introduction (Part I, pp. 1–15), individual sections set the compilation and its manuscript in context. Dorine van Espelo (Part II, pp. 16–79) considers how the eighth century went about the business of diplomatic correspondence, the tradition into which we should set the letters, and the logic of the lemmata. Richard Pollard and Richard Price explore the collection’s Latinitiy in Part Three (pp. 80–101). In Part Four (pp. 102–140) Rosamond McKitterick breaks new ground in her chapter on the Franks and the eighth-century papacy, and what role papal correspondence had to play in the interdependence of the Carolingian rulers and their papal supporters. There is a crisp introduction for each letter, which is also provided with helpful notes that send readers to parallel issues elsewhere in the letter collection and to further scholarship on issues of interest. An appendix (pp. 437–454) tracks down [End Page 180] the names and key biographical detail for all the individuals in the letters, while a glossary (pp. 463–468) assists newcomers with some of the collection...