Maya Maskarinec begins this volume by leading us on a walk around Rome in April 752. Classicists will be reminded of similar hikes through an earlier instantiation of the city guided by Diane Favro in The Urban Image of Augustan Rome (Cambridge University Press, 1996). Though Maskarinec is less interested in the kinds of questions about sight lines, routes, nodes, and spatial relationships that Favro derived from the work of urban planner and theorist Kevin Lynch, she is equally concerned to gauge the responses that the cityscape might have evoked from those living in or passing through it, in her case that means the city's local residential communities and early medieval pilgrims and travelers. Maskarinec's walk establishes two themes central to her study: first, saints and their relics were ubiquitous in eighth-century Rome and, second, inhabitants and visitors alike typically viewed the city and its sacred sites through eyes conditioned by stories of holy men and women, tales they had read or listened to on the feast days of the martyrs whose shrines they now attended. In the background of this eighth-century walkabout lurk two key sources, the ninth-century Einsiedeln itinerary, which plotted for its medieval readers a series of routes through Rome, and the passiones of the martyrs, not only those whose cults had long been resident in the city (on which see now Michael Lapidge, The Roman Martyrs: Introduction, Translations, and Commentary [OUP 2018]) but especially those whose relics had arrived more recently, primarily (but not exclusively) from the eastern Mediterranean. In this opening chapter, then, Maskarinec exposes the three main vectors that converge in this book, emanating from Constantinople, Francia and the late antique Roman past. It is the convergence of these byways of commerce in relics, tales, and collective memory that concerns Maskarinec, for it is there that she finds what is distinctive about early medieval Rome. Furthermore, she argues, it is this distinction--heightened by the sheer number of newly arrived eastern saints—that led so many contemporaries to view the Rome as "microcosm" of Christendom (4) and that lured so many pilgrims to the city, especially those Carolingian lay and clerical elites who arrived from north of the Alps. Conversely (and consequentially) it was back along hat same pathway that Roman history and the papal gaze began to turn, emblematically when in early 754 Pope Stephen II presented himself at the court of Pepin the Short in Paris.

To be clear, Maskarinec's broader argument is that the transformation of Rome in the later sixth and seventh centuries under the initiatives of post-Gothic war Byzantine administrators and Roman patrons--especially their introduction of so many eastern saints into the Roman cityscape--so significantly changed the city's image, and eventually Carolingian perceptions of it, that it became the physical and imaginative center of Christendom to a degree and in a manner unprecedented. "Rebuilding" Rome in the early middle ages, therefore, also entailed the restructuring of international diplomacy and politics. The argument is supported by three moves, first, accumulating evidence for church building, relic transfers, and relic assemblies in several regions of the city; second, coordinating that information with the contents and transmission histories of relevant passiones: and, finally, observing Rome through the lens of Carolingian documents and building projects in Francia. The story unfolds across seven chapters.

Chapters two through five are each devoted to one sector of the city: the Forum Romanum, Palatine Hill, Tiber waterfront, and Aventine Hill. (Those who wish to extend the inquiry to the Capitoline Hill can profitably turn to Jason Moralee'sRome's Holy Mountain: The Capitoline Hill in Late Antiquity [OUP, 2018].) In these chapters Maskarinec explores the "ecology" of Rome's sanctity, suggesting how newly arriving cults found their place, facilitating connections (synchronically) among Rome, Ravenna, and Constantinople and (diachronically) with the Roman past, Christian and pre-Christian. Between the early sixth and mid-seventh century the Roman Forum, which had long resisted Christian remodeling, was settled by a series of "saints in the service of empire" (50), most already enjoying popularity and imperial patronage in Constantinople: Cosmas and Damian, Sergius and Bacchus, the Forty Martyrs of Sebaste, Theodore of Pontic Amaseia, and Hadrian of Nicomedia. The patronage of popes and administrators "mapped" the churches and passiones of these Greek saints (the latter now in Latin translation) onto Roman self-consciousness and topography. Eighth-century popes--Paul, Hadrian, and Leo III--would continue to patronize both these sites and their saints, now thoroughly Roman. On the Palatine, Maskarinec stresses, matters were different in degree and tone. The period saw installation there of a single saint, one not from the East. At some point, presumably in the later sixth-century, an oratory dedicated to the late-developing and unfamiliar martyr Caesarius of Terracina was added to the imperial palace (the Domus Augustana-Flavia) by those who oversaw that complex for the emperor in Constantinople. The choice, as Maskarinec remarks (60-1), must have seemed odd and she draws our attention to a later tradition, given literary form(s) as the translatio S. Caesarii Romam, that rewrote history by fancifully crediting the emperor "Valentinian" and Pope Damasus with the import of Caesarius's relics. Whatever the original motives, by the eighth century, to which Maskarinec dates this tradition (Appendix 3), the translation of Caesarius to Rome had been re-imagined in a manner that expressed new-found papal self-confidence, a sentiment that would emerge more forcefully in the next century, although the site of Caesarius's Palatine oratory would long remain a Greek enclave.

The next two chapters follow a similar pattern, identifying and contextualizing new foundations and collating the relevant material evidence (architectural and epigraphic) and textual sources (hagiographic and liturgical) in order to explain how neighborhood "communities adjusted the past to the changing contours of early medieval Christianity" (105). Chapter four focusses upon the diaconiae of the Forum Boarium area, especially S. Giorgio al Velabro and S. Maria in Cosmedin, untangling very complicated building and administrative histories while arguing for a gradual shift from the private patronage of Byzantine functionaries catering to Roman and immigrant communities to papal control by the eighth century (the exception may be the late arriving, possibly eighth-century, S. Nicola in Carcere). The Aventine churches of S. Sabina and S. Bonifacio receive attention in chapter five. The former's journey from titulus to martyr's church and the latter's possible emergence as a center for Cilician refugees in Rome, perhaps as early as the seventh century, reveal further ecological permutations in the ways that "foreignness" might simultaneously serve Rome's local communities to establish individuality and foster integration into a wider Christian oikumene. Typically, the vignettes of these first chapters are insightful and draw their conclusions cautiously. Exemplary are the pages devoted to inter-leaving the epigraphy, visual imagery, and passiones of S. Sabina (105-09). Only occasionally does Maskarinec over-reach. The melding of the various passiones of St. George with the history of S. Giorgio al Velabro and its surrounding monumental landscape (the Arcus Argentariorum and the Janus Quadrifons) is overly dependent on summoning up the kind of generic (and here under-theorized) viewer and reader whose presence in the intial walkabout is less troublesome.

With chapter six City of Saints pivots away from the local towards the universal, first considering several Roman sites where, Maskarinec argues, the city's bishops engineered "collectivities of sanctity" by creating spaces in which large groupings of saints could be venerated en masse. Under such initiatives Rome was cleverly fashioned as "the home of all saints," heroic figures who in turn and in unison stood as a defense against threats physical (e.g., Lombards or Avars) or doctrinal (e.g., iconoclasm). Analysis highlights four sites: the S. Venanzio chapel of John IV (640-42); Gregory III's (731-41) All Saints' Oratory at St. Peter's; an eighth-century fresco, the "panorama of the saints," at S. Maria Antiqua, perhaps to be credited to Paul I (757-67); and Leo III's (795-816) relic collection at the Lateran. Such assemblies do stand apart from the work, much of it also papal, previously and still being done at the regional level. Although we might consider Symmachus I's (498-514) early sixth-century Vatican Oratory of St. Andrew, which boasted relics of a number of Italian (and extra-Roman) saints as well as those of the apostles Andrew and Thomas, to be a precocious precursor of such exercises in accumulation, Maskarinec makes it clear that such collectivities gained traction as eighth- and ninth-century popes "cultivated Rome's sacred topography" in part to catch Frankish eyes. Together with the increasingly common transfer of catacomb relics to intra-mural churches--so forcefully illustrated on the triumphal arch of S. Prassede, as Maskarinec points out (137)--this universalizing (and homogenizing) agenda stands out distinctly as a revision of late antique (Roman) constraints on the disruption of corporeal relics and the primacy of the suburban martyria.

Two final chapters, briefer and more impressionistic, take us to Carolingian Francia. Here, Maskarinec argues, Rome was being recreated in multiple media. The ninth-century Einsiedeln compilation (epigraphic sylloge, itineraries, catalogs, and a poetic anthology), produced at Fulda, is unpacked as "a guide to Rome for arm-chair readers" (140), one particularly intent on crafting Rome, past and present, as the unrivaled seat of empire and Christianity. Even more intriguingly, Maskarinec's close reading of Ado of Vienne's Martyrology reveals Ado's sheer ingenuity and inventiveness as he set about creating a universal martyrology that deftly constructed "a Rome centered-vision of Christian sanctity" (165). Words were seconded by relics as Rome found its way to Francia via other routes: Sergius and Bacchus found a home at Weissenburg; relics of St. George, a gift of Pope Formosus (891-96), at a new church in Reichenau. It will require fuller discussion and wider context to assess the proportionate role and impact of such ways of thinking and acting but we have here a powerful tool for reconstructing the mentalité and motives of Francia's elites.

City of Saints is a panoramic book, voracious in its appetite for a wide range of sources. Its vignettes of sites, saints, and documents are thoughtfully woven into a narrative that tells one story about how early medieval Rome became something late antique Rome was not and about how eventually that new Rome not only engaged but also responded to the interests and imagination of Carolingian rulers, bishops, and abbots. Maskarinec's story foregrounds saints who, for the most part, came to Rome from elsewhere in the sixth, seventh, and eighth centuries through the initiatives of administrators, clerics, and popes. The integration of those new cults into the city's neighborhoods helped to establish Rome's image as the "home of all saints." And they were surprisingly numerous. It requires seven pages to accommodate a (conservative) list of these "saints from abroad" venerated in early medieval Rome (Appendix 1). Twenty-one vivid color plates, twenty-five black-and-white images, maps, and plans make the story clearer and more enjoyable. There are, of course, other tales to tell about Rome and its image in these centuries (when, for example, so many Anglo-Saxons also found their way south) and City of Saints suggests more than one way of telling them well.