H.'s book is the seventh volume of the Edinburgh History of Ancient Rome series, preceded by C. Ando's Imperial Rome ad 193 to 284 and followed by A.D. Lee's From Rome to Byzantium ad 363 to 565. Evidently, this is a series that deserves to be on everyone's bookshelf – everyone who is interested in the Roman Empire and who is looking to be informed, enlightened, brought up to speed on the latest research and entertained by wonderful writing in the process.

Within the series, H.’s volume stands out. Covering the period beginning with the reign of Diocletian and ending with that of the emperor Jovian, the short-lived successor of Julian, aka the Apostate, who perished on the battlefields of Persia, H. engages with a crucial period of momentous administrative, military and religious change. For Edward Gibbon this period, beginning with Diocletian, signified a ‘new’ empire, and as such it has received an enormous amount of scholarly attention. The empire Diocletian (supposedly) initiated has been considered as the domain of tyrannical emperors, who relinquished the tolerant ways of their precursors, the turning point towards decline or, thanks to Constantine, the moment of Christian triumph. The period has been seen as altering the fate of a worn-down empire, exhausted by the so-called third century crisis, henceforth transformed into a realm marked by pagan–Christian hostilities and the deep divisions of inner-Christian disputes until it faded away into the post-Roman kingdoms. Of course, modern scholarship no longer holds these views in such stark terms, but their remnants have not yet vanished; indeed, they continue to reappear, in stronger or less strong terms, in different contexts (e.g. P. Athanassiadi, Vers la pensée unique: La montée de l'intolérance dans l'Antiquité tardive [2010]).

H.’s approach to this crucial time is innovative, both conceptually as well as on the level of detail. Without neglecting the novelties, she above all stresses the extent of the continuities that link the reigns of Diocletian, Constantine, his three sons (who are often given far less attention and space than they deserve) and Julian, the last emperor of the second Flavian dynasty, brought into being by Constantine. Though the reforms initiated by Diocletian and continued, refined and implemented by Constantine and Constantius II were extensive – a streamlined, provincial organisation, new forms of taxation intended to improve the collection of revenues, an expansion of the imperial bureaucracy, new monetary standards, a new imperial capital in Constantinople, a reorganised military and a ‘new’ religion – they nevertheless remained embedded in traditional structures. As H. concludes on p. 323:

H.’s individual chapters explicate and sustain these conclusions in a host of detailed observations and insights, too numerous to list. Proceeding chronologically, H. interweaves narrative with analytical chapters. Thus the long third century is followed in Chapter 2 by an account of the Tetrarchy up to 311, and succeeded by two chapters that offer succinct summaries and analyses of the changes mentioned above: provincial administration, the armies, taxation and finance, coinage and prices, law and morality, and the various approaches of the rulers to religion. Chapters 8 and 9, dealing with the sons of Constantine, are particularly incisive and combine an overview of their political challenges with a description of the army and the culture of warfare. Chapter 12 offers a very welcome appreciation of Antioch, the premier city during that time – Rome was no longer an active centre and Constantinople was too recent a creation. Chapter 11 is dedicated to the role of women in the period, beginning with the members of the imperial household. H. notes that the survival of the imperial women in the Tetrarchy and beyond depended on the success of their men, a chilling reminder of the dangers at the very top of the hierarchical pyramid (p. 258). Fausta's fate, allegedly murdered by her husband Constantine in 326 soon after the execution of his son Crispus, stands paradigmatic: the cause of her death has eluded modern scholars as much as ancient observers, a sign of the tight control Constantine exercised over the public image of his domus or household. Of course, that did not prevent speculation and interpretation; as H. notes, the various ancient accounts of her disappearance are modelled after the examples of Phaedra and Hippolytus, Joseph and Potiphar's wife, or Nero and his wife Octavia, depending on the author's assessment of Constantine and his reign. Thankfully, however, Fausta's fate was also the nadir; most female members of the imperial households were allowed to live even after their men had lost out in the struggles for supremacy, and most dedicated their lives to the furthering of Christian religious affairs, including significant building projects. Indeed, as H. points out, focusing on women in the law and their use of the law, many women were assertive participants in the shaping of their lives, elite women above all, but by no means exclusively so. Here, the example of female philosophers, both pagan and Christian, that is women known as ascetics, played a significant role, showcasing how women who controlled their assets could exercise increasing influence through patronage; and those opportunities only expanded with the spread of Christianity (p. 273).

For this reviewer, H.’s passages on the law – of which I give a very brief indication above – the administration and the taxation, are the most exciting in the book. Her summaries and overviews of these themes, in nearly each chapter, are exemplars of social history with a deceptive clarity that makes it easy to underestimate the depth of her engagement, and full of nuances easily missed by those less well informed than she is – and that would include a great many readers, I suspect. This is a wonderful companion to a crucial period, full of insights and fresh perspectives, and a joy to read.