To those studying thirteenth-century England, the politics of the period 1258-1267 are a well-trodden field. Most recently, the second volume of Carpenter's Henry III biography provided an extended account (David Carpenter, Henry III: Reform, Rebellion, Civil War, Settlement [2023]). With the period so well known, what can Coss add to our understanding? In the preface he states that his book is a celebration of the wealth of thirteenth-century studies produced since the creation of the Thirteenth-Century Conference. He also intends to provide a reinterpretation of mid-thirteenth-century English political history. Key to this reinterpretation are his two central arguments: firstly, that the events of 1258-67 were not “revolutionary” and are in fact better understood as a crisis within politics. Secondly, he argues that this crisis was generated and controlled by the aristocracy, and the agency of those further down the social scale has been overstated by modern historians.

Chapter 1 establishes Coss’s interpretive framework. Here, he aims to cast doubts upon “The whig interpretation” of thirteenth-century English politics. To do this he critiques extracts of Treharne's The Baronial Plan of Reform (Manchester University Press [1932]), which he views as the most influential work on the period. Although Coss mounts an effective critique, it is worth asking when was the last time historians read Treharne in any depth? Interestingly, he includes Treharne's dismissal of what in 1932 was the “traditional” interpretation of the period as one of baronial protest. In other words, while claiming to offer a reinterpretation of events, the crux of Coss’s argument represents a return to pre-1932 assumptions.

Chapters 2 to 4 offer a synthesis of existing scholarship on the state of the kingdom and Henry's kingship in the period leading up to 1258. There is little new material here, but in Marxisant mode there is a greater emphasis on the structures and systems that underpinned social norms. Chapter 2 explores Henry's kingship, finances and royal government. The following chapter looks at the familiar issues of patronage, Henry's relationship with the nobility, and the privatisation of justice, suggesting that Henry followed a policy of appeasement when it came to his nobility. Chapter 4 then examines the structure of magnate power at court and in the localities, using the Clare earls of Gloucester and Hertford and the Bigod earls of Norfolk as examples. Although this section views the period through a Marxist lens it is hard to find any new insights here.

Chapter 5 is arguably the most significant in terms of new offerings. Through a detailed prosopographical study, Coss suggests that the knights involved in the 1258 baronial movement did not provide the impetus for reforms. His study shows that the magnates played a significant role in the choice of “reformist” personnel and that, by and large, the knights chosen continued to act in traditional capacities rather than showing “revolutionary” fervor.

Chapters 6 to 8 examine the period 1258–67 in greater depth. Chapter 6 analyzes and illustrates the structures that underlay the baronial movement: faction, affinity, and party. Some sections, like chapters 2–4, feel all too familiar, but Coss’s prosopographical studies are detailed and impressive. Chapter 7 then analyzes local events during the civil war. Using extensive legal records, Coss indicates that the struggle on the ground was for power and control rather than a fight to maintain the principles of reform. While this chapter is persuasively written, one must question whether the legal records here utilized could possibly reveal the ideological motivation of the movement's participants. Moreover, Coss carefully glosses over the possibility of ideological motivation in order to advance his own thesis. Chapter 8 then re-examines Simon de Montfort and his support base. This chapter might have been better positioned after chapter 6, as the prosopographical study here complements the structural analysis of the role of factions, party, and affinity in the conflict.

Chapter 9 is one of the most crucial for Coss’s overarching argument. Building on work by Paul Brand, he examines the acts and legislation produced between 1258 and 1267. In this he highlights that the magnates, king, and justices were responsible for drafting the legislation, with both sides of the conflict seeking credit for what emerged. He argues that it is unlikely that the knights contributed much to this process, while acknowledging that the magnates were not deaf to the demands of their retainers. This raises a sort of chicken and egg dilemma, as there is always the possibility that the magnates were in fact responding to pressures from below, rather than ignoring their subordinates in order to push their own selfish agenda.

The final substantive chapter looks at the aftermath of the conflict and the first half of Edward I's reign. It synthesizes the traditional accounts of the resolution and focuses upon the disinherited. Coss then looks to Edward's reign and suggests that the new king sought to establish an equilibrium within the kingdom. Edward's patronage and legislation is discussed, and one cannot help but think that the processes lauded here are all too similar to Henry's “policy of appeasement” that Coss had criticized in chapter 4.

Overall, the book has an appeal for scholars and students alike. Coss clearly achieves what he set out to do in the preface. Aside from his prosopographical studies, however, he makes no very major contribution of his own. Rather, he provides a skillful (if selective) synthesis of the past forty years of thirteenth-century studies, offering an alternative, if occasionally warped, conceptual framework by which to understand the period. Arguably, the book's main value lies in forcing the reader to carefully consider accepted norms. While the reader may not agree with every claim, such re-evaluation is much needed in a field in which disagreement or debate are welcome alternatives to dull consensus.