Heinzen’s new Prisoners of War and Military Honour, 1789–1918 makes a valuable contribution to our understanding of military honor. His is a cultural history of honor, not an account of the conduct of war or the development of military institutions, although he touches on both.

As his primary indication of the standing and role of military honor, he centers on the treatment of prisoners of war and, more specifically, on the practice of parole. Dating back to the Middle Ages, elite warriors who accepted the surrender of an adversary could demand that their captive pay a ransom to achieve his release. The prisoner may have required his freedom to raise the required sum, so the captor could grant him conditional release on his adversary’s parole d’honneur, pledging not to take up arms again until he had paid the ransom. Over time, such parole became more broadly applied and more formally regulated by the state. During the early modern period, parole also applied to rank-and-file soldiers, although remained more common among officers. Paroled soldiers escaped confinement by giving an honor-bound promise not to bear arms again until they had been exchanged or ransomed. They might even be allowed to return home while on parole. Heinzen believes that the Enlightenment ushered in limited war, providing even more humane treatment of prisoners of war and extending the practice of parole.

Many claim that the French Revolution and the creation of great conscript armies replaced limited warfare with a “total war” that abandoned humane moderation. However, Heinzen argues that military honor retained its importance, and that parole, though less common, persisted in different forms during the nineteenth century. As an example of continuity, he references the parole of Lee’s Army of Northern Virginia by Grant at Appomattox in 1865, as well as evidence from the Russo-Japanese War (1905–1906). He also offers an interesting and revealing discussion of Freemasonry and how it served as a meeting ground for military officers. He first introduces this theme in his discussion of the Enlightenment, and shows how it endured through the nineteenth century and into World War I.

His discussion of prisoners of war also extends to the internment of “civilians” in colonial environments, with particular attention to the Boers during the Second Boer War (1899–1902). In this conflict, the British allowed burgers who swore an oath of neutrality to avoid internment and return to their homes. Heezen points out how this oath paralleled that taken by parolees. While the Hague Conventions (1899 and 1907) included provisions for parole, World War I saw few exchanges or paroles. Policies were complex and competing: for a time, the British banned paroles based on personal pledges yet allowed them in special cases, such as for the sick and wounded. Heinzen underscores his emphasis on honor and parole by discussing what he terms “small parole” – the practice of allowing groups of POWs to go outside the wire under escort. These forays by honor-bound prisoners offered temporary relief from the prison environment. Beyond this, Heinzen maintains that reliance on military honor steered international warfare in more humane directions from the mid-nineteenth century to the present day.

Heinzen’s work demonstrates an impressive command of a broad range of sources, but aspects of his narrative and analysis remain troubling to this reviewer.

Heinzen endorses the commonly held view of eighteenth-century “limited war”, epitomized by the works of Vattel and others. In doing so, he neglects counter opinions, most relevantly Paul Vo-Ha’s important Rendre les armes. Le sort des vaincus xvie–xviie siècles (Champ Vallon, 2017). Vo-Ha attacks the reality of limited war, what he characterizes as guerre en dentelle (lace war) during the eighteenth century. Heinzen lists Vo-Ha’s book in his bibliography, but mentions it only once in the text.

Moreover, Heinzen says little about parole, ransom, and exchange before the Enlightenment, seemingly implying that the concern for prisoners and the provisions of prisoner exchanges and parole was not significant before the eighteenth century. Yet, the formal responsibility of warring parties to care for prisoners and offer parole goes back to the cartels of the seventeenth century. Cartels were formal agreements or treaties between warring parties during a particular war detailing the provision of protections and services to prisoners of war, mechanisms of prisoner exchange between adversaries, and offering parole. He uses the word “cartel” a few times in the text but is so dismissive of the subject that it does not even merit a place in his index.

It should also be noted that one factor encouraging the humane treatment of prisoners was their value in exchange. Cartels often dwelt in detail on the ransom and exchange of prisoners. An adversary holding prisoners could exchange them for his own troops held by the enemy. Here, honor was not the issue, but the use of soldiers as chits in exchange deals. An undernourished, sick, or lame prisoner would be of limited value in bargains struck.

Parole could also result from something other than confidence in military honor. Heinzen mentions this but does not give it sufficient emphasis. In the Russo–Japanese War, for example, adversaries were motivated less by mutual honor and trust than by hopes of enhancing the prestige of their armies in international conflict. Granting parole could also be a convenient and practical recourse in the midst of war. For example, after the fall of Vicksburg in July 1863, General Ulysses Grant paroled some 30,000 Confederate prisoners because he lacked the resources to hold or transport them to prisoner of war camps in the north. Grant nevertheless paroled the entire bag of prisoners, even though Union forces had been forbidden, since May 1863, from paroling or exchanging Confederates, for reasons explained below. For Grant, parole was a practical necessity rather than a moral imperative. Heinzen makes no reference to Grant at Vicksburg.

This points to another problem. Heinzen is highly selective in his treatment of the American experience. His study of honor and prisoners is explicitly a work of European history, yet he invokes American influences and examples where they help his case. For example, he discusses at length the 1863 Lieber Code of American military law and practice as an influence on humane international law. He also mentions that General Grant awarded pardons to Lee’s defeated Army of Northern Virginian at Appomattox. Yet, these pardons were not protections from imprisonment, but rather a way to end the Civil War without further fighting. In fact, the Civil War began with the warring parties concluding the Dix-Hill Cartel of 1862, which echoed eighteenth-century cartels in providing parole. However, the Union Forces stopped allowing parole in May 1863 in response to the Confederacy refusing to exchange Black American troops they had captured. The Southern cult of White Supremacy considered Blacks not as soldiers but as escaped slaves. Without full access to parole and exchange, both adversaries had to construct large prisoner of war camps, the most notorious of which was Andersonville. This transformation of prisoners’ lives certainly deserves some discussion in Heinzen’s work but goes unmentioned.

Another aspect of early Civil War parole raises another neglected issue: the need for warring parties to create camps for their own men who had been released on parole but had yet to be exchanged. One of the Northern camps was established at Columbus, Ohio; another at Annapolis, Maryland. The largest Confederate parole camp was located at Demopolis, Alabama. This is where the parolees from Vicksburg were sent to await exchange. Such concentrations of parolees certainly made exchanges more manageable. However, they also forcibly retained parolees who might otherwise simply go home. To the extent that this latter rationale applied, parole could have constituted not a respect for, but a denial of, military honor.

My final concern is the rarified tone of Heinzen’s book. He has written an intellectual and cultural history of honor, primarily viewed through the prism of parole. His cultural emphasis brings with it an elevated vocabulary that will leave many a military historian scratching their heads, as in his discussion of Judith Butler’s work: “[B]orrowing from J.L. Austin, she further differentiates between illocutory and perlocutory performances in which the former creates new realities while the latter involve speech acts whose realization is contingent on favorable conditions” (p. 212).

My critiques should not be read as condemnation but as caution. Heinzen’s book offers such a rich collection of details and such an intriguing argument that, for me, it is a must read in the history of prisoners of war. It is regrettable to me that Heinzen’s volume was not available to me before I published my own Leaving the Fight: Surrender, Prisoners of War and Detainees in Western Warfare (Cambridge University Press, 2025).