The volume under review is an incisive and timely contribution to the study of both ancient religions and human-environment relations. Through a series of thematic discussions, Ailsa Hunt argues that ‘sacred trees reveal Roman theological thinking in action’ (14) and, in doing so, challenges some of the scholarly lynchpins of Roman religion. H. urges a departure from legalistic approaches to sacrality, whilst also aligning with emergent scholarly inquiry on theological thinking in the ancient world, e.g. E. Eidinow, J. Kindt and R. Osborne (eds), Theologies of Ancient Greek Religion (2016). Most important, however, is H.’s substantiated refutation that Roman intellectual engagement with trees — and the wider natural environment — was a ‘country bumpkin subject’ (293). Instead, H. illustrates the many ways in which trees contributed to the complexity of religious thought and prompted communities to engage urgently with challenging theological questions.

Following introductory discussion (chs 1–2), H. confronts Roman conceptions of trees’ sacrality in ch. 3, with an especially rich analysis of the ficus Ruminalis. H. argues that the mortality of trees was central to their religious materiality and further expounds on this theme in ch. 4, on arboriculture and arboreal deaths. This chapter includes a valuable evaluation of the Arval grove, a matter to which I will return later. Ch. 5 continues to address the sentience of trees by examining arboreal agency and how ancient communities might imagine the divine in the unruly behaviour of trees. Of particular value here is H.’s perceptive appraisal (177–90) of the term numen and the ‘theological value’ (178) of the word's indefinability. Finally, ch. 6 explores the ‘diverse spectrum of ways in which trees might stand in relation to a particular deity’ (224), including sections on gods and tree types, arboreal epithets and statues, and trees in cult space. The volume clearly covers an array of topics important to the study of ancient religions.

H. often utilises wide-ranging material to explore thematic questions, travelling between Rome, Pompeii, Arcadia and Delphi to discuss arboreal statues, for instance (255–65). Yet H. also focuses on some specific case studies and it is here that the volume is strongest, because doing so elevates the trees to the forefront of discussion and reveals what they might contribute to the overall evidence-base. H.’s discussion of the Arval grove, a cultic complex a few miles outside Rome, is a representative example (135–72). Inscriptions from the grove detail the activities undertaken by the fratres Arvales for Dea Dia, including twenty-seven texts concerning the grove's trees — helpfully collated in the Appendix (295–301). H. devotes much attention to a particular sub-group that records the Arvals offering expiatory sacrifices for pruning the grove during a May festival (137–52). The standard interpretation of these texts maintains that the pruning act directly necessitated the sacrifices: the Arvals needed to prune the grove and were then obliged to atone for a violent act against the goddess’ sacred trees. H. successfully challenges this explanation from many angles and is most compelling when highlighting the detriment of tree pruning in May (150–2). As a result, H. proposes that the Arvals’ pruning was ritual, not practical, and thus prompts further questions about the religious mentalities underpinning such sacrifices — the responses to which have ramifications beyond the Arval grove.

H.'s study has thus far received two significant critiques, both of which require attention. C. Houlbrook, Time and Mind 10.3 (2017), 323–5, highlights many comparable studies from other disciplines to challenge H.’s proposal that trees have not received serious scholarly recognition. Yet, in the field of Roman religion, scholars are noticeably reluctant to engage with sacred trees. Indeed, H. artfully explores the history of this reticence in ch. 2, charting the enduring distaste for sacred trees from the comparativism of the nineteenth century through to the indifference of the present day. According to H., the assumption that trees were simplistic in the Roman imagination has gone unquestioned throughout the centuries, such that scholars now either dismiss the notion of sacred trees as animistic or accept their existence without critical engagement (66). Though some scholars are approaching sacred trees (and natural environments) with increasing nuance and sensitivity, much work remains to be done and H.’s volume is a worthy contribution to this endeavour.

The second critique is proffered by C. E. Schultz, Classical World 110.3 (2017), 435–6, and concerns H.’s treatment of ‘Roman religion’. In particular, Schultz questions the extent to which the volume examines ‘Roman religion’, when H. relies on Greek sources of the Roman period. In my opinion, H. satisfactorily addresses this particular concern in ch. 1 (22–5); but I do think that the notion of ‘Roman religion’ would have benefited from further expansion. Specifically, H. might have aligned her definition of ‘Roman religion’ — ‘shorthand for the diverse religious experiences of those living within the Roman world’ (23) — more closely with the volume's emphasis on ‘theological thinking’. Throughout the study, H. demonstrates that the inhabitants of the Roman Empire were thinking theologically through trees, but there is scope here to make bolder conclusions about how this phenomenon might then sit within a ‘revived’ picture of Roman religion more generally. As H. admits, ‘this book is not all about trees’ (292). Instead, it uses trees as a conduit to examine how Roman individuals and communities grappled with ‘challenging theological questions that took them to the heart of their understanding of where they stood in relation to the divine’ (2–3); a matter of enduring relevance to all scholars of ancient religions.