Almost fifteen years ago, Beate Dignas and Engelbert Winter’s book Rome and Persia in Late Antiquity represented a novelty in the context of the study of Roman history. Until then, the role of the Sasanian Empire in Roman history had almost never been thoroughly analyzed by historians, a lacuna that this book sets out to emend. Since 2007 interest in this subject has gained momentum and there are now several substantial scholarly monographs dealing with the complex and sometimes obscure relationship between the Romans and the Sasanians. Peter Edwell’s book follows in the footsteps of this rich (albeit recent) line of research. This is Edwell’s second monograph on the relationship between Rome and its eastern neighbor. While his first book focused especially on the first three centuries AD, this new one pushes the analysis well into the fourth century.
The first chapter and general introduction set out the aims and the chronological framework of the book, which is “principally focused on the military and political (mostly diplomatic) relationship between the Roman Empire and the Sasanian Persian Empire from the emergence of Ardashir as Shahansha to the last years of the reign of Shapur II” (p. 2). Also, information on the methodology and the sources used is provided. Here Edwell highlights the usual problem in this kind of work: the imbalance between the available Greek and Latin sources and those in other languages, skewing the narrative toward a Roman perspective.
Chapter 2 covers the period of the first confrontations between Romans and the Arsacids, from the age of Sulla to the reign of Caracalla. It serves as an introduction to the main topics of the book and it does not add much per se for students who are familiar with Edwell’s previous work, though later on it proves useful for understanding the author’s main argument. The chapter highlights the importance of Parthian internal political factors in determining the external military policy of the two empires confronting each other.
Chapter 3 begins the analysis of the core subject of the book, addressing the rise of the Sasanian dynasty and its confrontations with Rome until the age of Philip the Arab. Edwell here introduces a point which will prove to be one of the most interesting in his monograph: the continuity between Parthian and Sasanian attitudes toward Rome. In the early confrontations between the new Sasanian Persian regime and Rome, two elements of the old opposition between Rome and Parthia remained: the importance of Armenia and the centrality of Mesopotamia (p. 80). The Roman military approach was similar: punitive actions evolving into major invasions. Both empires were engaged in military endeavors at the opposite ends of their territories: while the Sasanians were expanding in the Persian Gulf and on their eastern frontier (support for the Kushano-Sasanian kingdom), the Romans were on the defensive on the Danube and the Rhine.
Chapter 4 deals with the 250s and 260s, during which the Sasanians gained the upper hand against the Romans: while the Roman Empire was struggling against many internal crises, Shapur I emerged as the Iranian emperor, and he proved to be a strong and cunning leader. It is noteworthy that here Edwell rightly questions the recent tendency in scholarship to closely connect the crisis of the Roman Empire with environmental and health problems, as exemplified by Kyle Harper, who has recently stressed the effect of the so-called plague of Cyprian on the empire. While conceding that such a plague may have played a role in deepening the crisis, Edwell wisely plays down its importance as a factor for Roman defeats by the Iranians, since “it is obvious…to note that such a devastating pandemic disease would not respect imperial borders…and that Persians…would be equally susceptible to it” (p. 88). The chapter underlines how the major victories earned by Shapur I in the 250s and 260s were not followed by territorial gains for the Persians. In fact, the main goal of the Sasanian emperor was the taking of captives, both military and civilian, to be relocated within his empire and used as manpower.
Chapter 5 carries the analysis to the end of the reign of Carus. Edwell summarizes how during this period, while the Roman empire had reached its nadir in terms of stability, unity, and power, leading to the breakaway empires in Palmyra and Gaul, the end of the reign of Shapur I opened a period of relative instability in the Sasanian Empire as well. Meanwhile, Rome began its recovery and, after the successful restoration of the empire’s unity under Aurelian, the emperors started to plan regularly—and, in the case of Carus, to actually carry out—military actions against Persia.
Chapter 6 is focused on the age of Diocletian, whose political and military reforms are analyzed as far as they are relevant to the general argument of the book. In particular, Diocletian’s reorganization of the eastern frontier is the object of lengthy discussion. Also, the confrontation between Diocletian and Galerius, and Narseh in the final years of the third century, is carefully examined. The chapter has a strong Roman perspective, and it sees the Diocletianic reorganization of the oriental limes as a direct response to the Persian threat. Also, the author concludes that the treaty of 299 was not as favorable to the Romans as it could have been, since Diocletian did not think it feasible to extend direct Roman control deep into Iranian domains.
Chapter 7 addresses the reigns of Shapur II and Constantine. Here a new element is introduced: the role of religious beliefs. At this time the confrontation had lessened since the Romans were satisfied with the peace treaty of 299 and Shapur II had to concentrate on internal business. Nevertheless, Constantine renewed the conflict with the Sasanians and this would prove a crucial fact in the following decades, opening a strong debate among contemporaries whether Constantine’s eastern campaign was ultimately the origin of Julian’s disaster of 363.
Chapter 8 analyzes the conflict and diplomacy between Constantius II and Shapur II. This is a better documented period compared with previous ones, but as is often the case, the imbalance between the Greek and Latin sources on the one hand and those in all other languages gives us a strong Roman perspective. For his part, Constantius II ended up being criticized by both pagans (because he was Christian) and Christians (because he was Arian, and therefore a “heretic”). The chapter focuses chiefly on the infamous Persian campaign of the emperor Julian and its consequences. It is almost a stand-alone piece and is probably the most interesting of the book. It starts with a reconstruction of Julian’s personality. The author later explains at length the problems in using the sources on Julian: religious issues make it almost impossible to reconstruct the events in detail since Julian (more than any other emperor) was object of a heated quarrel between pagan and Christian writers. The preparation for war and the various stages it went through are reconstructed in detail by Edwell, who never forgets to give reasons for the discrepancies in the available sources and always offers his interpretation of controversial events. The last part of the chapter focuses on Jovian’s peace treaty with the Sasanians, its reception in the sources, and its consequences in the subsequent period.
The conclusion summarizes the main points of the book. Especially interesting is the conclusion that the Romans tended to ignore the differences between the Parthians and the Persians, as is evident from the imperial victory title Parthicus Maximus, which was still in use well after the rise of the Sasanian dynasty. Also, Edwell tries to downplay the usual scholarly distinction between the Parthians’ wariness of military confrontation with Rome and the more aggressive stance of the Persians. Instead, he sees a major continuity in terms of foreign policy between the two phases of the Iranian empire. Finally, Edwell clearly and rightly underscores once again how Armenia represented the main object of competition between the two great empires from the Republic until the fourth century.
Overall the book is interesting, well written and thoroughly researched. The author makes good use of Parthian/Persian sources to give a picture as complete as possible. He also understands very well the complexity of reading and interpreting the sources and puts them in their own historical and cultural context. Still, the general structure of the book is definitely Romanocentric, as one can see from just the chapter titles and the chronological partition of the narrative, which is governed by Roman history.
The book also succeeds in giving a satisfactory—and sometimes meticulous—account of the military competition between the two empires, and in providing enough context to understand this military history in the wider background of the Romano-Persian relationship. One notable exception is trade, which is only addressed at any length for the post Diocletian period (pp. 158-60). It would have been interesting to consider the topic for the previous periods and to give reasons for any possible change (or continuity) that characterized the post-Diocletianic age. In addition, trade is addressed in hardly more than a page of text, not enough to give even a general idea of the importance of ancient trade between Rome and Persia and its effect on both economic and political issues.
These are only minor criticisms, unrelated to the core of the book. Edwell is to be praised for providing a scrupulous account of the period 193-363, offering a clear picture of the events, and analyzing all the available evidence, including inscriptions and coins. The choice of ending the work in 363, in the aftermath of Julian’s oriental expedition, leaves the reader in the middle of a somewhat incomplete narrative. It would have been interesting to see how the situation kept evolving down to the age of Anastasius I and the building of Dara, which compensated the Romans for the loss of Nisibis in 363. But this probably would have made the book too lengthy.
In conclusion, Edwell’s work represents a valuable addition to the current scholarship on a subject that is becoming more and more important to our understanding of Late Antiquity. It is readable and thoroughly researched, and many students of ancient history will find it extremely useful.
 See, e.g. B. Dignas, Rome and Persia in Late Antiquity: Neighbours and Rivals (Cambridge: CUP, 2007); G. Fisher, Rome, Persia and Arabia: Shaping the Middle East from Pompey to Muhammad (London and New York: Routledge, 2019); and P. Pacor, Roma e Persia: due imperi a confronto. Cinque secoli di battaglie, conquiste, trattati e coesistenza(Rome: Aracne, 2021).
 The first was P. Edwell, Between Rome and Persia: The Middle Euphrates, Mesopotamia and Palmyra and the Coming of Rome (London and New York: Routledge, 2008).
 K. Harper, “Pandemics and passages to Late Antiquity: Rethinking the Plague of c. 249-70 described by Cyprian”, JRA 28 (2015): 223-60.
 Ammianus’ Res Gestae is a key source for this period, especially regarding the Persian invasion of Mesopotamia in the years 359 to 360.
 It is worth noting that the author states that the Romans levied a tax of 25% on imports (tetarte), but omits that at some point after the reign of Aurelian, this tax was halved to 12.5% (octava).