In Das frühe Sasanidenreich und Rom: Eine Forschungskritik Karin Mosig-Walburg offers a rigorous, lucid, and comprehensive assessment of recent scholarship on two related topics: Roman-Sasanian relations in the third and fourth centuries, from the emergence of the Sasanian dynasty through Šāpūr II's defeat of Julian in 363, and internal Sasanian politics during the same period. The work supplements Mosig-Walburg's important monograph of 2009, Römer und Perser vom 3. Jahrhundert bis zum Jahr 363 n. Chr., discussing the scholarship on Roman-Sasanian relations during the period in question that has appeared since the publication of Römer und Perser, as well as addressing internal Sasanian politics in a more substantial way than Mosig-Walburg's earlier volume had done.

Following a brief introduction, Mosig-Walburg allots two chapters to each of her two topics: a relatively short introductory chapter, which offers an overview of the topic in question, as well general observations about trends in the scholarship; and a substantially longer and more detailed discussion, where Mosig-Walburg proceeds methodically from point to point, engaging with individual scholarly works at length. After these four chapters - two for Roman-Sasanian relations and two for internal Sasanian politics - we find an appendix, where Mosig-Walburg discusses several books and articles in greater depth.

Among the book's highlights are Mosig-Walburg's critical discussions of several widely-held views, whose background, implications and connections with other problematic assumptions she traces sensitively and persuasively. One such discussion, which takes place primarily in the first two chapters, but which is resumed on various occasions throughout the book, deals with the question of early Sasanian territorial ambitions: to what extent can Šāpūr I (r. 240-270) and the other Sasanian rulers of the third and fourth centuries be considered to have acted "aggressively" vis-à-vis Rome, pursuing expansion whenever and wherever possible? As Mosig-Walburg marshals an array of citations to demonstrate, this is indeed a view one encounters very often - that from the reign of the dynasty's founder Ardašīr I (r. 224-240) onwards, Sasanian rulers had an abiding interest in expanding their territory at Rome's expense (pp. 108-112). And this view, Mosig-Walburg perceptively notes, is closely related to other notions: not only that the Sasanians sought to recreate the Achaemenid empire, as the third-century Roman authors Herodian and Cassius Dio maintain, but also, somewhat less obviously, that, insofar as all the early Sasanians generally sought western expansion, if a given ruler did not act aggressively against the Romans we can assume he was impeded from doing so: whether by his own ineffectiveness, Roman strength, or internal turmoil (25-37, 108-156). Although Mosig-Walburg's discussion is largely taken up with responding to and criticizing other scholars, an important positive point can also be discerned: Sasanian rulers should be approached on an individual basis, with an eye to the specific problems and situations they faced and according to a careful reading of the available sources, rather than as the interchangeable exponents of an essentially uniform policy and ideology. This is, of course, a challenging undertaking, due in large part to the problems the source-material presents, but it is not a hopeless one; as Mosig-Walburg shows, building on points made in her Römer und Perser, an attentive reading of Šāpūr I and Narseh's (r. 293-302) inscriptions, in particular, belies the idea that these rulers' policies with respect to Rome can be accounted for in terms of some inveterate "aggression," or certain majorly expansionist ambitions with common ideological underpinnings which every Sasanian šāhānšāh since Ardašīr had held.

Another valuable discussion deals with the question of Šāpūr I's "tolerance" and "liberalism" as opposed to some of his successors' "illiberal" and more strongly pro-Zoroastrian tendencies - exemplified above all by the divergent fates of Mānī, the founder of Manichaeism who would be executed at Wahrām I's (r. 271-274) behest, and Kerdīr, the prominent Zoroastrian priest of the later 3rd century and author of several monumental inscriptions. Mosig-Walburg argues that the idea that Wahrām I and II were distinctly tougher on the Manichaeans and more supportive of Zoroastrianism than Šāpūr and his short-lived son and successor Ohrmazd I (r. 272-273) is largely unwarranted; while Šāpūr's extensive discussion of temple-foundations and sacrifices in his inscription on the Ka'ba of Zardosht alone should leave his Zoroastrian allegiance beyond question, the Manichaean accounts of Šāpūr's sympathy for their religion should be viewed somewhat more skeptically than they have been, and even in these sources there are indications that things had already taken a bad turn for Mānī and his followers before Wahrām I took power (pp. 517-48, 619-58). Mosig-Walburg's discussion raises many important points, and makes for a good complement to the broader critiques of the application of concepts such as "intolerance" and "liberalism" to the Sasanian empire and other ancient states advanced by scholars such as Adam Becker and Richard Payne. Nonetheless, it should be said that the relationship between Zoroastrianism and Manichaeism as she presents it is insufficiently dynamic; in maintaining, in response to Jason BeDuhn, that Kerdīr, being "the representative of a religious tradition that already looked back on a long history," would not have seen Mānī's appropriation of Iranian traditions as a serious threat (631-632, n. 403), she fails to address BeDuhn's broader argument - which itself builds on his important 2015 article "Mani and the Crystallization of the Concept of 'Religion' in Third Century Iran" as well as the work of P. Oktor Skjæ'rvø (e.g., his 1997 article "Counter-Manichaean Elements in Kerdīr's Inscriptions: Irano-Manichaica II") - that the third century was a formative period for Zoroastrianism and Manichaeism alike, in the course of which the two traditions were shaped decisively by their interactions with one other.

Across Das Frühe Sasanidenreich und Rom's 760-odd pages of text, we encounter countless corrections and refutations of other scholars' work. Although many if not most of these criticisms are more or less on the mark, in at least some cases what Mosig-Walburg presents as a matter of (her being) right and (someone else being) wrong seems rather to reflect a reasonable difference of opinion, proceeding from methodological differences rather than sheer error on someone's part. A case in point is Mosig-Walburg's criticism of Jill Harries' assessment of the emperor Julian's campaign against the Sasanians - that in launching this campaign his "precise intentions and motivations were mixed." Rather than making what would seem to be an entirely uncontroversial assumption regarding any historical actor, Harries, by Mosig-Walburg's account, in fact "falsely communicates the impression that there is trustworthy information regarding a whole series of reasons and intentions which we can in good conscience ascribe to Julian" (381). It is often with salutary effect that Mosig-Walburg deploys her understanding of what the sources do and do not say, and accordingly what can be accepted as a "fact" and what is mere "conjecture," but her approach can also be unduly rigid, and betray questionable methodological presuppositions on her own part - that, for instance, a ruler such as Julian's actions and motivations can and should be explained entirely by recourse to his own words as relayed by Ammianus Marcellinus.

Altogether this is a rich and important work, which scholars of late antique Rome and Iran alike would do well to consult. The service Mosig-Walburg provides lies not only in her perceptive discussions (and, in many instances, convincing criticisms) of individual works of scholarship, but also in her meticulous indexing of the manifold points of disagreement and discussion that have characterized and in many ways constituted early Sasanian history as a field of study, and will doubtless continue to give rise to spirited debate for the foreseeable future.

Thomas Benfey