The volume provides a thorough and valuable insight into the complex nature of Roman military command and sheds greater light on core Roman principles often taken for granted. The text in this regard effectively builds upon D.'s previous work Imperium, Potestas and the Pomerium in the Roman Republic, which re-examined the scope and definition of imperium; Commanders and Command builds on this re-examination with a particular focus on the importance of provincia and key developments in the usage of the term across a considerable span of Roman history. Although Roman military command has received renewed examination in recent years, most notably from Brennan, The Praetorship in the Roman Republic (2000), and Richardson, The Language of Empire (2008), a more all-inclusive study of provincial command has been lacking in recent scholarship. D.'s thesis proposes that ‘military command was not a single, monolithic idea in the Roman mind but was defined by different and malleable attributes’ (p. 6), with changing attitudes to, and conceptions of, provincia being principal to explaining the development of Roman military command across the period in question. The initial three chapters focus on the key concepts and traditions of Roman military command and authority down to 367 b.c., attempting to decipher earlier notions from the limited source material, whilst the latter four chapters account for particularly significant developments in their usage from 367 b.c. to the early Principate. The choice of 367 b.c. to divide the work into two sections seems appropriate given the enacting of the lex Licinia Sextia which restored the consulship and marked an important shift away from the traditional and more broadly defined commander role of the early Republican praetors.

D. sets out his comprehensive study of Roman provincial command by noting that such an undertaking ‘is difficult because its origins lay in the republic's legendary beginnings, for which we have little reliable evidence’ (p. 1). Any study of early Rome has to deal with events and phenomena which cannot be ascertained with accurate precision and this is especially problematic with an investigation of this nature. Early notions of provincial command and commanders, D. argues, bear hallmarks of the later Republic, where authors, notably Cicero and Livy, considered earlier times with regard to their own contemporary period. Whilst this makes the study problematic, the plethora of examples provided enable us to piece together better how command structures worked in early Rome. This wealth of examples continues throughout the book and gives the volume the coverage necessary for a work of this magnitude and, moreover, accounts for various anomalies that emerge throughout Roman history. The value of this becomes clear upon consideration of the command involved in the war against the Cimbri in the late second century b.c. Whilst W.V. Harris notes the difficulty in ascertaining the nature of provincia in this case (War and Imperialism in Republican Rome 327–70 bc [1979], p. 150), D. is able to go further in his assessment by building on the framework established throughout his work (p. 317). As such D.'s work not only serves to catalogue the changes of Roman provincial command across many centuries but also provides the vital context to help build a convincing overall argument.

The work continues by examining the fundamental concepts of potestas, auspicium and imperium and the spheres militiae and domi in an attempt to ground our understanding of later developments in the basic principles which defined Roman command. In this section, D. reaffirms his stance from his earlier work that ‘imperium did not, under normal circumstances exist within the pomerium, but rather that it was strictly extra-mural military power’ (‘Imperium, Potestas and the Pomerium in the Roman Republic’, Historia 56.4 [2007], 419). D.'s consideration of space in Roman thought towards the role and function of their magistrates, gives an important basis for the concepts discussed in the section. By not only considering the use and limits of the concepts themselves, but also their application in the two spheres militiae and domi, the work is able better to interpret the role, function and scope of Roman magisterial authority. Although such terms can carry a broad range of definition into which one can easily become embroiled, D. effectively steers the discussion towards the implications of the terminology on our consideration of aspects of military command. Such a decision is only natural given the focus of D.'s work, but a greater consideration of the wider choice of terminology in the sources may have added greater credence to the arguments being raised. Although associated terms such as provincialis are somewhat uncommonly utilised by ancient historians (J. Richardson, The Language of Empire: Rome and the idea of Empire from the Third Century bc to the Second Century ad [2008], p. 100), their more frequent appearance in the later literature perhaps could have provided further evidence of the changing definition of provincia. However, given the great depth of material covered and evidence deployed in D.'s work and the recent examination of terminology provided by Richardson, it is perhaps unsurprising that such an issue receives less attention.

Subsequent sections of D.'s work aim to place later developments in Roman military command in the context of the military expansion and social and political upheaval of the mid to late Republic. Chapter 5 explores the early changes to the concept of provincia towards constituting an area of Roman control by examining the particular case studies of Sicily, Sardinia, Corsica and Spain. The choice of focusing on these particular provinciae evolving out of third-century b.c. conflicts is useful to aid our understanding of this particular development and unsurprisingly the importance of annexing former Carthaginian territory comes through in the chapter. The tremendous importance and impact of the Punic Wars of the third century b.c. for Rome provides a useful context in which such changes occur; the correlation between changing conceptions of Roman military command and upheaval in Rome also features later in the text. Case studies, however, tend to be naturally selective and a comparison with an area of early Roman operation such as Illyria, where this shift was not so apparent, may have provided another layer for analysis. Nevertheless this shift towards a permanent form of provincia is expounded upon effectively in subsequent chapters with a discussion of the effect of political change in the Late Republic, leading to a preference towards permanent provinciae, the amalgamation of multiple provinciae and consequently more expansive military campaigning. D. stresses that the political condition of the Late Republic ‘drove men to experiment with the ideas of imperium and provincia in their search for political advantage and success’ (p. 343) and that these changes, even when initiated on an ad hoc basis, came to influence later Roman ideas regarding provincial command. The effect of the political upheaval of the Late Republic on the nature of command has often been highlighted, but by contextualising the development of command conceptions in the political upheaval of the Late Republic, D. presents a compelling scenario where both affect one another in tandem. This scenario provides an effective setting for the intricate manipulation of the associated concepts and conceptions in the imperial period.

The volume is comprehensive and informative whilst the methodology utilised provides a useful means of dealing with the limitations of the surviving historical record. By building on his previous work on the subject and providing extensive coverage, D. presents a persuasive case regarding the nature and development of concepts of Roman command. As such concepts were fundamental throughout Roman history, this work will prove useful to scholars and enthusiasts alike for years to come.