This volume aims to fill a gap in the field of Byzantine studies by drawing together over fifteen analyses of various, distinct phenomena relating to Byzantine epistolography. Each study demonstrates engagement with current research trends either by developing insights into long-established epistolographical themes, such as friendship and friendship networks, or by identifying and introducing more innovative topics like epistolographic performance and rituals of epistolary exchange. This multi-authored Companion contains much that will interest classical audiences (despite the necessary focus of the book on later periods), both for its survey of late antique epistolography and for the rich evidence it provides for the later history of the broad epistolographical tradition that began in the late antique eastern Mediterranean.

As M. Grünbart pointed out, there are two types of Byzantine letters: those written on papyri and those on parchment, and they are separated in time (‘Letters, Letter Writing, Byzantine’, in R.S. Bagnall et al. (edd.), The Encyclopedia of Ancient History [2013], p. 4027). The second type begins where the first leaves off, in the eighth century, with a period of overlap in which both were probably produced but neither survive in any great number. Indeed, no original Greek literary letter survives from before the ninth century. Before then, few literary letters were produced, and those that survive – such as the letters of Gregory of Nyssa, Basil of Caesarea, Gregory of Nazianzus, Severus of Antioch, Maximus the Confessor and a range of other monks and bishops – display a classicising style. The primary focus of this Companion is therefore on middle to late Byzantine letters. The reason for this, according to the editor, is ‘a pragmatic one’ (p. 13): while much excellent scholarship has been conducted on late antique and early Byzantine letters and letter collections, a wealth of later Byzantine source material remains relatively ignored. References to earlier evidence are thus rarely found beyond the volume's two initial contextualising chapters and the final chapter.

Riehle sets the stage with an introductory essay sketching the history and patchy historiography of Byzantine epistolography. While scholarship on New Testament letters dominated the field of epistolography until the 1980s, P. Hatlie and M. Mullett were among the first to see the potential in the understudied sources of Byzantine letters. Hatlie's seminal article, ‘Redeeming Byzantine Epistolography’ (Byzantine and Modern Greek Studies 20 [1996], 213–48), demonstrated that letters were more than an ivory-tower pastime of Byzantine intellectual elites and could offer valuable information to cultural as well as literary historians.

The first section, ‘Contexts for Byzantine Epistolography’, offers background surveys of classical letters, letters from late antiquity and early Byzantium up to the ninth century, and Latin letters in the golden age of letter-writing in the medieval West. T.J. Bauer offers a useful history of Greek and Latin letters from their very beginnings up to the documentary letters of late antique Egypt. This chapter complements recent scholarly interest in letter collections of late antiquity, including the critical introduction and reference guide of C. Sogno, B. Storin and E. Watts (edd.), Late Antique Letter Collections (2017) and P. Allen and B. Neil's synthesis, Greek and Latin Letters in Late Antiquity (2020). Bauer's discussion of pseudepigraphy across various letter-types merits attention.

J. Tannous's chapter contains an encyclopaedic treatment of Syriac epistolography and retrieves from obscurity several key letter-writers of the seventh and eighth centuries, including Athanasius II of Balad, Jacob of Edessa and George, Bishop of the Arab Tribes. This chapter will complement the analysis of earlier Syriac letters in B. Neil and P. Allen, Conflict and Negotiation in the Early Church (2020). Tannous's passing references to Arabic letters and letter exchanges with Arab leaders are echoed in several later chapters. Concluding this section is L. Wahlgren-Smith's illuminating study of medieval western collections of eleventh- and twelfth-century scholastics, starring key churchmen like St Bernard of Clairvaux, Gerbert of Aurillac and Peter Abelard. Across all three chapters, the importance of philia/amicitia as a motivation for letter-writing emerges as a uniting theme (even if the concept of Christian amicitia spilled over into erotics in Peter Abelard's correspondence with the schoolgirl-nun Eloise).

Part 2, ‘Byzantine Letter-Writers in Context’, puts the spotlight on two of the best-known figures of Byzantine letter-writing – Michael Psellos and Demetrios Kydones. These literary giants merit a chapter each, due to their prominence as letter-writers in their respective periods. The literary outputs of these figures have already been studied in some depth, but to feature their contribution to epistolography is a useful exercise. As F. Bernard notes, the letters of Psellos were transmitted as a scattered corpus rather than as a uniform edition and played an important role as a model for future Byzantine epistolographers. Psellos used letter-writing to build and maintain an extensive social network with individuals from all levels in society and adapted his register to suit the addressee. His letters dealt with a range of practical matters, including career management, monasteries and taxes. They were couched in a discourse of philia, an ideal of friendship that implied commitment to intellectual ideals in parallel with the amicitia that governed letter-writing in the medieval West in the same period. In his letters Psellos represented himself as a philosopher, but one ‘ridden with problems and doubts’ (p. 139). While Bernard's and F. Leonte's (respective) studies on the letters and contexts of Psellos and Kydones are certainly integral to comprehending the more thematic and conceptual analyses that ensue, the precise justification for the inclusion of these chapters is not made clear. J. Preiser-Kapeller's chapter in the final section builds on M. Mullett's foundational study, Theophylact of Ochrid. Reading the Letters of a Byzantine Archbishop (1997). Preiser-Kapeller visually maps the archbishop's extensive correspondence according to letters, localities and individuals as a series of ‘ego-networks’. The absence of further case studies, including a planned contribution on the collection of the monk Theodore the Stoudite, leader of the iconophile resistance, is regrettable (as Riehle notes, p. 21). A sustained treatment of the political correspondence of Photius, ninth-century patriarch of Constantinople, is also a desideratum.

Part 3, ‘Forms and Functions of Byzantine Epistolography’, comprises ten essays on an impressively diverse spectrum of topics, ranging from diplomacy and codes to philosophy and didacticism. The focus on themes and concepts, rather than specific figures or time periods, attests to the volume's usefulness as a ‘companion’. Each author's analysis of several metalinguistic aspects of letter theory and practice – its relationship with philosophy; use as a vehicle for self-representation; its performativity; its role in enacting friendship and didacticism; its sometimes obscure communication codes – is corroborated by individual letters and letter-writers. This approach allows readers to grasp the concept at hand with ease and encourages them to apply these concepts to their own research. N. Gaul's study of the performance of letters in formal assemblies and learned salons (theatra) presents some of the most novel material in the volume. His inclusion of many brief references to a range of lesser-known Byzantine sources is highly valuable for introducing the less-experienced reader to a glossary of new material. Another example is the fragmented Epithalamion cited by C.J. Hilsdale in her treatment of Byzantine artworks, including manuscript illuminations, which prove a rich source for the rituals associated with epistolary exchange (pp. 391–99).

In an engaging essay on ‘The Epistolographic Self’ S. Papaioannou distinguishes four kinds of letters: real, rhetorical letters; biblical or theological letters; literary or invented letters; and embedded letters, found in biographies, histories and hagiography, and often invented (pp. 337–8). The latter category, embedded letters, has been virtually unexplored to date, but C. Cupane makes a welcome start with a study of letters embedded in narrative literature, especially the romance texts from the Komnenian and Palaiologan periods. Hilsdale's chapter shows how images from Byzantine art can be used to supplement the fragmentary material record, and how much they have to tell us about the social form, function and perception of letters in Byzantine culture and particularly in the political sphere. Few female authors appear in the record, in proportion to the relative paucity of surviving sources. Their activity as letter-writers and recipients was significant in the medieval West and the Byzantine East, as the chapters of Wahlgren-Smith, Hilsdale and Cupane show.

In the final essay, ‘Letters and New Philology’, Riehle returns to letters composed before the ninth century. He shows how epistolography was a vital part of the formation of the Christian canon of Greek patristic works (p. 486) and makes a brief comparison with classical Latin letter collections. The main focus of this chapter is on the appropriation of the New Philology approach from classical studies by medieval scholars, and from there to Byzantine studies, with a short section on New Philology and Byzantine epistolography (pp. 477–84). The chapter then moves to the principles underlying letter collections. The origins of Greek self-edited collections are, as Riehle admits, ‘more difficult to trace’ (p. 481). Riehle's attempt to track continuity between the classical and Byzantine worlds is to be applauded. A greater emphasis on the ruptures between classical, late Roman and Byzantine epistolary practice would have been an additional asset here and throughout the volume. The rupture with pre-Christian traditions is particularly noticeable in the range of gifts that accompanied the later Byzantine exchange of letters, which were for the most part directed to an equally narrow range of aristocratic recipients.

The bibliography provides a handy compilation of most recent scholarship in the field up to 2018. The primary source list in the bibliography includes only translated texts, not critical editions (p. 503), no doubt a necessary shortcut in a collection of this size. Recent editions of texts not available in modern translations are included in the bibliographies at the end of individual chapters.

In his first-century ce tract on style (Peri hermeneias / De elocutione) Pseudo-Demetrios of Phaleron famously characterised letters as ‘icons of the soul’. Using a wide range of sources from Byzantine literature, codicology and art, the eighteen essays collected here show the many aspects of the Byzantine soul that were refracted through their letters and their impact on the wider society. Riehle is overly modest in his claim that this volume functions not as an ‘exhaustive handbook’, but as an ‘eclectic guide giving orientation, raising questions, and providing inspiration’ (p. 21). It certainly fulfils his wish that the volume will ‘contribute to furthering our understanding of epistolary culture in Byzantium and beyond’ (p. 21). Undoubtedly eclectic, the volume delivers a highly comprehensive and engaging range of studies exploring innovative subjects that any astute scholar of middle to late Byzantine history will appreciate.