This is an important book. The product of many years of research on the late antique and early medieval episcopate, it seeks fundamentally to revise our understanding of the role of bishops in early medieval politics. Broadly stated, it is Moore's contention that bishops played a key role in the evolution of the office of kingship within the Frankish realm, leaving a legacy that would be felt for many centuries to come.

After a brief introduction, the study proceeds roughly chronologically, with the first two chapters dedicated to the role of bishops in late antique Gaul. Here Moore traces how, following the conversion of Constantine, bishops were increasingly integrated into imperial government, placing them in a position to take over key social and political roles once the empire began to falter in the fifth century. Indeed, it was in a large part the constancy offered by the office of bishop that ensured the survival of episcopal authority when so much else changed beyond recognition. However, as Moore notes, bishops did not remain unaffected by developments. Rather, the regionalisation of politics which ensued upon (or caused, depending on one's perspective) the ‘Fall of Rome’ encouraged the development of a distinctive conciliar tradition within Gaul. Indeed, it is at these councils, Moore observes, that we can best observe the growth and development of a more coherent conception of the episcopate as a corporate group. The rise of the Franks in the early sixth century naturally had implications for this and it is to this subject that Moore dedicates his third, fourth and fifth chapters. The first examines the relationship between early Frankish kings and their bishops, which Moore characterises as close, but strained: whilst the Merovingian realm was founded in no small part on cooperation between the king and Church (as illustrated by Clovis's baptism), the two sat rather awkwardly side-by-side. The contours of this relationship can be traced in Gregory of Tours's writings: though not hostile to kingship per se, Gregory was by no means enthusiastic about the royalty of his day. Nevertheless, Gregory also held out hopes that kings might come to take on a more responsible and indeed ‘episcopal’ outlook and the fourth and fifth chapters of this study examine the evidence for precisely such developments. The former argues that by issuing written (Latin) laws and undergoing unction Frankish and Visigothic kings came to adopt a more religious perspective on their office, while the latter discusses how the liturgical role of bishops served to underpin their growing socio-political significance.

Moore's study comes into its own as it moves into the Carolingian period, to which chapters vi–ix are dedicated. The first of these focuses on the missionary and reforming efforts of Boniface and his contemporaries, which were enthusiastically supported by the early Carolingians. It was, Moore suggests, in part by taking on responsibility for the mission (itself headed by bishops such as Boniface) that the Carolingians opened the door for episcopal influence on conceptions of kingship. The rise of the Carolingians to royal (751) and then imperial (800) dignity provided further impetus, as chapter vii demonstrates. Here a rhetoric contrasting Merovingian incompetence with reforming Carolingian zeal was used to justify their elevation to the kingship. Thus it was, Moore contends, not so much ‘political Augustinianism’ which led to the development of a conception of a ‘sacred kingdom’ in these years so much as active cooperation between kings and bishops, which led to royal office being understood in ever more episcopal terms. Chapter viii then traces how this cooperation reached its dizzying heights under Louis the Pious: in this period bishops were able to establish themselves as independent players to a degree hitherto unimaginable. However, the trials and tribulations of Louis's reign were also a taste of things to come and following the break-up of the Carolingian empire bishops were rarely able to operate on quite the same scale. Still, in many important respects they did not lose ground: a ‘sacred kingdom’ had been formed and bishops had carved out a niche for themselves which was to endure into the central Middle Ages and, indeed, beyond.

Overall, this is a well-written and convincingly argued study. While there is little new in the assertion that Christian thought played an important part in the development of kingship, Moore's emphasis on the role of episcopal models for royal office is both novel and engaging. His command of the secondary literature is impressive and his readings of primary sources are nuanced. However, the study's lengthy gestation – it is in effect a revised version of the author's 1993 PhD dissertation – seems to have meant that a number of important recent publications are not given the acknowledgement that they deserve. To give a (by no means exhaustive) list: the discussion of the role of bishops in the late imperial judicial system does not cite Kevin Uhalde's study of the phenomenon; the discussion of Gregory of Tours's attitudes towards Chilperic makes no mention of Guy Halsall's article on the subject; the analysis of the Bonifacian mission does not cite any of James Palmer's works; the chapter on Charlemagne makes no reference to Rosamond McKitterick's book on the subject (not to mention Wilfried Hartmann's); the section on Carolingian attitudes towards images makes no mention of Thomas Noble's Images, iconoclasm, and the Carolingians; and the discussion of Lious the Pious's penance cites Mayke de Jong's Penitential state, but not Courtney Booker's Past convictions. Even more inexplicable is the absence of any reference to Eugen Ewig's seminal ‘Zum christlichen Königsgedanken im Frühmittelalter’ (1956), a study whose implications for Moore's arguments are clear. Whilst some of these omissions are slight (and it may be that the fault here lies not with the author, but with the Press for sitting too long on the manuscript), others are more fundamental. It is, therefore, unfortunate that elements of this otherwise exemplary study were out-of-date before it ever reached print.

Still, it would be wrong to end on such a negative note. This is a subtle, well-argued monograph that will greatly enrich our understanding of the early Middle Ages; it should be required reading for anyone interested in the religion and politics of the era.