Recent years have seen a welcome revival of interest in Roman constitutional studies, and two major treatments of Republican command structures have now appeared in quick succession, namely Frederik Vervaet's The High Command in the Roman Republic (2014) and the work under review. Whereas Vervaet starts from and builds on orthodox, Mommsenian conceptions, much of Fred Drogula's approach is radically heterodox.

D. is at his most iconoclastic in his treatment of imperium. In ch. 2, he argues (as earlier in Historia 56 (2007), 419–52) that imperium, rather than, as usually supposed, denoting the totality of the higher magistrates' powers, was a strictly military authority, to be sharply differentiated from their civil power (potestas): imperium was conferred after entry into office through the lex curiata; dictators could exercise it within the city, but consuls and praetors only took it up when departing for their province, and could not exercise it in the city except on the day of their triumph or if authorized by a senatus consultum ultimum. D. also maintains that there was no gradation in the strength of the various magistrates' imperium: although their offices differed in prestige, dictators, consuls and praetors all held exactly the same imperium (142–209). This conception of imperium leads D. to regard it as of less significance than provincia, which forms the primary focus of his work: ‘the provincia was the main concept that defined — and therefore limited — the scope of each commander's authority, and as such it was a far more dynamic and malleable idea than imperium’ (377).

Rejecting the traditional account of the double consulship as immediately replacing the kings, D. holds that in the first years of the Republic military command was exercised merely by aristocratic clan leaders. In time, perhaps from 449 b.c., the Roman state acquired a monopoly over the appointment of military commanders, and the Licinio-Sextian reform of 367 b.c. reduced their number, not, as our sources claim, to two consuls and a praetor, but to three praetors of equal power and status (ch. 1). The assignment of provinciae probably originated as part of the state's assertion of its control over aristocratic warlords, since commanders were thereafter only permitted to use the full force of their imperium within their provincia and conflict between commanders was normally avoided by assigning them to different provinciae (ch. 3). Chs 4–5 deal with various developments from the late fourth to the second century, including prorogation and the emergence of permanent provinciae and of controls on provincial governors. Consuls and praetors, D. argues, were differentiated in title and prestige (but not imperium) during the third century, and praetors normally provided the governors of permanent provinces, while consuls continued to receive wars as their provinciae. Ch. 6 considers various developments of the late Republic, and the final chapter discusses how Augustus ‘used successive interpretations of the provincia and imperium to craft his principate’ (381).

D.'s work thus offers a bold and challenging synthesis of a wide range of themes, but controversy is likely to focus in particular on his conception of imperium. Other scholars have recently maintained that imperium was military in origin and down-dated the separation of consuls and praetors to the third century, but D. goes much further in arguing that throughout the Republic imperium remained ungraded and exclusively military. These claims face formidable obstacles in the ancient sources. D. is obliged to dismiss or explain away numerous passages referring to the imperium of consuls or praetors where it is naturally interpreted as denoting the totality of their powers, civil as well as military, and also a substantial body of texts which speak of consuls as having greater imperium than praetors and dictators greater than consuls. To take just two examples, D. (165) misinterprets Cic., Leg. 3.9, which in fact equates the power of a dictator with that of the two consuls together, and is unduly dismissive (190–2) of the authority of the augurs Cicero (Att. 9.9.3) and Messalla (ap. Gell. 13.15.4), citing respectively the augurs' books and the second-century writer Tuditanus: whether or not they were correct to conclude that a praetor could not preside at elections, these authors and their sources evidently took it for granted that a consul's imperium was greater than that of a praetor. Also problematic is D.'s handling of magistrates' entitlement to lictors and fasces: he acknowledges that dictators were entitled to twenty-four, consuls to twelve and praetors to six, but insists that this differentiation related merely to prestige rather than imperium, and that it was only outside the city, when accompanied by axes, that fasces constituted insignia imperii (a claim clearly incompatible at least with Cic., Rep. 2.55). Nor are these the only difficulties: D. takes no account, for example, of the levy, an activity conducted by the consuls within the city, but surely by virtue of their imperium.

On provinciae, D. has many insightful contributions to offer, for example on the differentiation between consular and praetorian provinces. However, he exaggerates the impact of Gaius Gracchus' law on the consular provinces (298–304): more consuls came to be assigned overseas to permanent provinces from the later second century not because of the changed timing prescribed by that law, but because of the reduced opportunities for warfare in Italy, where most consuls had previously been deployed.

Although some aspects will inevitably be contested, D.'s erudite study constitutes an important and stimulating contribution on a major aspect of Roman Republican history which has long provoked debate. The controversy has indeed been running even longer than he acknowledges. Although he has mastered the vast subsequent bibliography, D., like most scholars working in this field, takes Mommsen's account as his starting point. In many respects, however, Mommsen gave canonical expression to an earlier consensus. One of his most eminent predecessors had taken a very different view of imperium, envisaging it as exclusively military on lines strikingly similar to D., namely the greatest Renaissance student of Roman antiquities, Carlo Sigonio (De antiquo iure civium Romanorum (1560) I, §§20–1; W. McCuaig, Carlo Sigonio: The Changing World of the Late Renaissance (1989), 209–19).