Bibliography for the reign of Julian ‘the Apostate’ has expanded considerably in recent years and as such the appearance of a volume which brings together the findings of historic and contemporary research into Julian's life, writings and legacy is clearly to be welcomed. The editors have assembled an impressive team of (overwhelmingly male) commentators whose contributions range widely over a variety of topics including Julian's military campaigns (Heather; Bleckmann; McLynn), Julian's writings including his legal constitutions (Nesselrath; Riedweg; Schmidt-Hofner; Vossing), his religious renovations and reforms (Wiemer; Bradbury) and his historic legacy and wider cultural influence (Marcone; van Nuffelen; Rebenich).

The opening chapter by Rebenich and Wiemer highlights the polarised responses of commentators concerning the significance of Julian's life and reign. In this regard, Julian continues to be judged by scholars either as a dynamic figure, a reformer of imperial government guided by the highest standards of Hellenic culture, or as an imperial usurper who behaved haphazardly in matters of the empire's military security and religious well-being. One reason for this historic division of opinion is that a biographical approach has dominated the study of Julian, an inevitability in light of the fact that Julian left behind a body of literature in which his thoughts and motivations were ostensibly disclosed to his audience. Commentators have therefore nearly always passed judgement on Julian even when they have sought to evaluate him objectively. The opening chapter offers a useful survey of modern scholarship on Julian, and the editors make the case for eschewing a biographical approach in favour of examining Julian according to recent trends whereby his identities as emperor, author, legislator, philosopher and commander are discussed (29). The Companion broadly achieves its stated aim to explain Julian's actions according to ‘their respective contexts’ (29) and in this regard the more successful chapters in the volume avoid ‘the spectre of incomparability’ (29) which has so often accompanied work on Julian. The arrangement of the following chapters feels a little awkward: their order appears to have been determined by the accepted chronology for Julian's life, which highlights that biography cannot be entirely avoided.

Heinz-Günther Nesselrath's chapter comprises a helpful survey of Julian's principal philosophical writings, namely his Letter to Themistius, the two invectives against the Cynics (Against Heraclius and Against the Uneducated Cynics) and the Hymn to the Mother of the Gods and the Hymn to King Helios. The chapter unpicks Julian's idiosyncratic interpretation of certain philosophical currents circulating during the mid-to-late fourth century, although it is somewhat surprising in light of the avowed editorial aim of the volume that more was not said about how these texts informed and in turn shaped Julian's own philosophy of rulership. The omission of the brief yet highly significant Consolation to Himself on the Departure of the Excellent Salutius is also perplexing in light of the evident rhetorical and philosophical orientation of the work (cf. J. Lössl in N. Baker-Brian and S. Tougher (eds), Emperor and Author (2012)). The recipient of that work had been a figure of support to Julian during his time campaigning in Gaul, a subject which forms the basis for Peter Heather's chapter. Heather presents a detailed account of Julian's role in facilitating the conflict in the Rhine region and offers a series of valuable counter-arguments to John Drinkwater's revisionist The Alamanni and Rome 213–496 (2007). Heather's contribution carefully explains the complex military and political situation that Julian faced during the late 350s, which was only finally resolved with the death of Constantius in November 361. The period leading up to the emergence of Julian as Augustus is the subject of the following chapter by Bruno Bleckmann. It thoughtfully evaluates the sources for this brief period of time in addition to reconstructing the course of events from the time of Julian's Parisian elevation in 360 (not 361: 112). Bleckmann's contribution clarifies the reasons for Julian's actions and the course of his rebellion and (in contrast to Heather's approach on Gaul) places less emphasis on re-evaluating prior assumptions and ideas about the episode. In this regard it offers a traditional companion approach to Julian's usurpation.

By contrast, Sebastian Schmidt-Hofner's lengthy chapter (124–71) is fully aligned with the editorial ambitions of the volume and is possibly the only contribution which successfully undermines the notion of Julian's incomparability. Here, Julian emerges as an imperial legislator of a fairly routine kind with a focus on issues handled by his imperial predecessors, e.g. the operation of city councils (the ‘problem’ of curial service), thereby challenging the notion of Julian's exceptionalism trumpeted by Libanius et al. This is not to claim that Julian failed to recognise the ‘propagandistic’ value of law in helping craft his imperial persona (128), and in the matter of tackling systemic corruption and religion Schmidt-Hofner's contribution highlights the declarative purpose of Julian's rulings. There is some overlap with Konrad Vössing's following chapter tackling the thorny subject of Julian's so-called ‘School Law’. While Vössing correctly notes the innovative quality of Julian's initiative demarcating the moral suitability of higher-level teachers, the author successfully situates Julian's reforms in an ongoing debate about the moral value of literature in curricula, one shaped by Christians for many years. Hans-Ulrich Wiemer's chapter performs an excellent service in slaying a number of sacred truths about Julian's religious reforms. He establishes successfully the renovative character of Julian's policies, but also establishes convincingly that Julian's own understanding and experience of traditional cult was limited (225). Julian's innovative plans for an empire-wide priesthood are discussed and the role played by Julian's identity as pontifex maximus is judged to underpin the rationale for the emperor's policies. The debt Julian owed to Constantine's understanding of religion is appropriately highlighted (236–7). Julian's complex interpretation of Christian theology is the subject of Christoph Riedweg's chapter. He offers a very close reading, similar to Nesselrath's approach in his chapter, of the emperor's fragmentary Against the Galileans. The innovative exegesis performed by Julian's work in separating the narratives of Plato's Timaeus from Genesis is duly noted, a factor resulting in Julian's contradictory assessment of the Jews and their god. Julian's interest in Judaism focalised through his intention to restore the Temple in Jerusalem forms the basis for Scott Bradbury's chapter. This is one of the genuine highlights of the Companion. Written with exceptional clarity, the chapter presents a masterful treatment of the sources for Julian's initiative and situates Julian's proposal within his broader ambition for the restoration of sacrificial practice in the Christianised landscape of the post-Constantine era (277). Neil McLynn offers a valuable chapter about Julian's doomed Persian expedition, a contribution which moves beyond established approaches for the campaign by focusing on Julian's motivations for the war and the representation of the war's principal events in a number of key sources (Libanius’ Or. 18, Ammianus and Zosimus). The final three chapters survey pagan responses to Julian (Arnaldo Marcone), the Christian reception of Julian (Peter van Nuffelen) and the early modern and contemporary reception of Julian in philosophy, literature and drama (Stefan Rebenich). Van Nuffelen's chapter in particular performs an important service by offering an early attempt to collate evidence of anti-Christian initiatives seemingly sponsored by Julian's policies in Christian hagiographical traditions (382–92).

The volume as a whole is a welcome addition to the field. A limited number of chapters (notably those by Heather, Schmidt-Hofner, Bradbury and van Nuffelen) build on developing approaches to emperorship by contextualising Julian's actions, policies and initiatives within the political, cultural and military exigencies of empire. The Companion as a whole therefore walks a fine line between on the one hand simply restating the idea of Julian's exceptionalism and on the other undercutting this notion by highlighting areas of continuity with his Constantinian predecessors, while also drawing attention to those periods in his reign when Julian was behaving in a genuinely radical way.