The book is the author’s revised Habilitation thesis, submitted at Rouen in 2013. It has no modest aim: Cadiou sets out to overturn the conventional account of the Roman army in the first century BCE. For him, that account is built on three planks: that Marius in 107 revolutionised military recruitment by allowing landless citizens (capite censi or proletarii) into the legions; that soldiers in the first century BCE were largely volunteers looking to make military service a career; and that these first-century soldiers were overwhelmingly recruited from the proletarii. This account largely derives from Gabba and is echoed by Gruen (who downplays the political aspects); a glance at chapters in relevant Companions by Erdkamp and Cagniart shows that, with some nuance, this is still the account undergraduates learn. Cadiou devotes a chapter to each of these planks, with the aim of tearing them down. In this aim he is largely successful.
Methodologically, Cadiou prefers contemporary and near-contemporary writers, in the belief that their incidental remarks are less likely to be anachronistic than the accounts of imperial authors. He uses Cassius Dio’s mistaken explanation of evocati at 45.12.3 as an example of such anachronism. Cadiou is consciously reacting against old frames of reference, arguing that scholars are predisposed to see the late-republican army as an imperfect prototype of the much better known (and better studied) army of the early Empire, and that this predisposition shapes our interpretation of, e. g., the quite sparse archaeological record of the first-century BCE army. We “see” a high level of equipment and weapons standardisation because we expect to see it.
Moving to the body of the text, Chapter 1 responds to Sallust’s statement (Iug. 86.2) that, in 107, Marius recruited volunteers from the capite censi; this has been central to most scholarly accounts of the first-century army. Cadiou is not the first to downplay the significance of these reforms, as he concedes, pointing especially to Rich. In the first chapter, Cadiou reinforces these existing arguments against the Marian reform, presenting it rather in the context of Marius’s immediate need for haste. But if the “Marian reform” is no longer seen by specialists as the revolutionary act which ushered in the proletarian army, this does not seem to have diminished the scholarly consensus that a revolution took place. But that is precisely what Cadiou is arguing against.
In chapter 2, he is more ambitious, aiming to demolish the idea that the first-century army was composed principally of volunteers. His argument here is convincing: there is very little evidence for volunteering (apart from the private armies raised by non-magistrates, e.g., in 87, 83 and 43) and almost every example of recruitment we see is by means of conscription. This argument builds on Brunt, but Cadiou goes beyond him in his nuanced treatment of resistance to conscription. A general obligation to serve did not mean that the Italian countryside was routinely scoured by press gangs. Exemptions (vacationes) were frequent, which Cadiou rightly suggests would have reduced resentment, as did the recognised importance of leave. That we do not see 1914-style joyful enthusiasm at the levy does not mean it was opposed: military service was a dangerous and serious undertaking. Cadiou tries hard to argue away evidence of resistance to conscription, which he thinks is concentrated in the 40s and due to wariness about joining the wrong side in a civil war. These arguments are not always successful, but they do point to the continuing importance of conscription as a practice.
Chapter 3 takes issue with a view which Cadiou ascribes to Gabba and Harmand, that the first-century army contained a very large proportion of proletarii. He is on solid ground here, building on earlier arguments against the view that the census rating for military service had been lowered in the second century; such arguments only ever made sense in the belief that the property requirement was abolished altogether in the first century, for which we have no evidence. Even the well-attested difficulties in completing the census need not have impacted significantly on its capacity to organise military service by property class.
Cadiou is strongest in this chapter when examining the literary evidence, principally Cicero. While this evidence represents soldiers as “poor” (whatever that means), it does not show they were landless proletarii. Criticism of the soldiers’ poverty is almost always political rather than social, while the debates over Antony’s judiciary bill show that even solid citizens of the First Class could be “poor” in Cicero’s eyes. Overall, the literary evidence tells us almost nothing about soldiers’ real socio-economic circumstances and everything about our elite authors’ contempt for “the poor”, i.e., everyone below equestrian level. Against this, Cadiou presents the evidence for some level of wealth among the soldiery; particularly convincing is the presence of personal property, including slaves, on campaign. The weakest part of this chapter is Cadiou’s attempt to downplay the significance of veteran land hunger, and a misguided attempt to prove that not only did many soldiers in the 40s have property (which he shows easily), but that they had a lot of property (which I do not think is shown convincingly). That said, it is clear that many men of the First Class show up in the legions. Having dismantled the idea that proletarii dominated the first-century army, Cadiou finally considers whether it contained any proletarii at all; his (very cautious) conclusion is that it probably did, with little evidence either way. Finally, mention must be made of a noticeable absence in the book: how little discussion there is of the enfranchisement of Italy and the doubling of the citizen population. Cadiou tantalisingly suggests that the formula togatorum may have formed the basis of regional recruitment after the Social War, but there is little else on this important question.
The author’s conclusion is that “l’armée romaine dite «post-marienne» est un mirage historiographique,” a conclusion amply justified by the argumentation throughout the book. As Cadiou repeatedly emphasises, existing scholarly discussions of the relationship between army and society hinge on the assumption of a proletarian army in the first century. With this now overturned, that earlier scholarship, as valuable as it is, will need to be understood in a new light. Cadiou has not given us a coherent new account of the late republican army, but he has demolished the old one. If we accept his broader argument, as I think we must, then our next task is to create this coherent new account.
Cadiou is right that the republican army has not attracted as much scholarly attention as its imperial successor, but his book will take its place in the wider recent project to understand how republican Rome waged war. But the book’s most important impact will be on the necessity to reimagine the story of how the Republic fell. Our old picture of the army—a proletarian soldiery which followed its generals against the state—is still so often repeated, and so central to our common understanding of first-century history, that Cadiou’s book must be made more widely known. Rumour has it that an English translation is being contemplated. If so, it is sorely needed. Anglophone scholars do not pay as much attention as we should to Francophone scholarship, but we need to pay attention to this.
 Gabba, Emilio. Republican Rome, the Army, and the Allies. Translated by P. J. Cuff. Oxford: Blackwell, 1976; Gruen, Erich S. The Last Generation of the Roman Republic. Berkeley, Calif.: Univ. of California Press, 1995; Cagniart, Pierre. “The Late Republican Army (146-30 BC).” In A Companion to the Roman Army, edited by Paul Erdkamp, 80–95. Malden: Blackwell, 2007; Erdkamp, Paul. “Army and Society.” In A Companion to the Roman Republic, edited by Nathan Rosenstein and Robert Morstein-Marx, 278–96. Blackwell Companions to the Ancient World. Malden: Blackwell, 2006.
 Rich, J. W. “The Supposed Roman Manpower Shortage of the Later Second Century B.C.” Historia 32, no. 3 (1983): 287–331. See also Taylor, Michael J. “Tactical Reform in the Late Roman Republic: The View from Italy.” Historia 68, no. 1 (2019): 76–94.
 Brunt, Peter A. Italian Manpower 225 B.C.-A.D. 14. Oxford: Clarendon Press, 1971.
 Harmand, Jacques. L’Armée et le soldat à Rome, de 107 à 50 avant notre ère. Paris: A.J. Picard et Cie, 1967.
 Armstrong, Jeremy. War and Society in Early Rome: From Warlords to Generals. Cambridge: Cambridge University Press, 2016; Taylor, Michael J. Soldiers and Silver: Mobilizing Resources in the Age of Roman Conquest. Austin: University of Texas Press, 2020.