As the editor of the superb recent Oxford University Press five-volume edition of its minutes and papers, Chad Van Dixhoorn, notes, “The Westminster assembly [of divines] has been the elephant in every history” of the 1640s (Minutes and Papers of the Westminster Assembly, 2012, 1:xiii). Much of this neglect was due to inherent problems of source material. Because the handwriting of Adoniram Byfield, the assembly's scribe, was so appalling, and because the debates were so vast—nearly 1,400 plenary sessions and more than 200 ad hoc committees—almost all historians relied on partial and unreliable transcripts or on more accessible pamphlet materials discussing the assembly's activities. But unwillingness to engage with the assembly's proceedings was also the result of a widespread assumption that it was, in the greater scheme of the Civil War era, a sideshow. A fractious meeting of windbag clerics endlessly discussing theological and ecclesiological minutiae compared poorly to major parliamentary debates, constitutional upheavals, and military operations. The greater willingness to integrate theology and politics shown by recent generations of scholars of seventeenth-century England has begun to tip the balance back towards taking clerical activity seriously. Nevertheless, Van Dixhoorn's edition has fundamentally opened up the field, and Hunter Powell's book is one of the fruits associated with the Cambridge-based project that created it.

The Crisis of British Protestantism represents an exceptionally detailed, fine filigree reading of the Westminster assembly's proceedings to two main ends. The first is to attack any lingering sense in the historiography of “a coarse polarity” (2) between Presbyterians and Independents. Powell repeatedly emphasizes that “Each polity had a variety of permutations,” and that we should understand contemporary debates in terms of a “spectrum” of positions. Thus “Presbyterianism in England was clearly variegated” (83). Van Dixhoorn stresses “the fluid dynamics of theological groupings’” in his splendidly pithy introduction to the Minutes and Papers of the Westminster Assembly (1:21), and Powell develops this in a more extensive and detailed fashion, albeit on a very particular front: a close analysis of different understandings of church power, based ultimately on contested readings of the key scriptural proof texts, Matthew 16:19, and Matthew 18: 17, 18.

The second end of Powell's work is to draw out what he sees as the neglected, or misunderstood, importance of the “Apologists,” the five authors of the Apologeticall Narration (1644), more usually known as the Dissenting Brethren. The intellectual trajectories of the members of this group are painstakingly excavated, and their role in debates minutely analyzed. Powell's contention is that by utilizing the materials of the Minutes and Papers of the Westminster Assembly systematically, and by taking great care to consider the “framework of intellectual discourse” (13) within which the debates were conducted, he can correct earlier misinterpretations of the substance and style of the assembly. He regularly attacks previous scholars for approaching the debates through published pamphlets, often written by men who were not members of the assembly, and who were therefore not constrained by its members’ commitment to secrecy. He is also hostile to what he regards as excessive deference to the views of the Scottish commissioner, Robert Baillie, whose readily accessible edited letters have long been a mainstay of scholarship. Overall, Powell wishes to argue that the Apologists were powerful, reasonable figures, propounding a vision for church settlement that was largely scuppered by clerical English Presbyterians—the real villains of his tale—and the shifting tactical concerns of the Scots commissioners.

How convincing and significant is all this? Powell's mastery of the content of the debates is impressive. He is especially good at exposing the times when members of the assembly silently quoted or recycled their own works, or those of others, not least to bypass difficult questions in a debating context. Better yet, as this suggests, he works hard to take seriously the methods and approaches of scholastic humanism that were second nature to the clerics involved in the debates. On this basis, what might appear to us to be savage disagreement can be reframed as a vigorous pursuit of better understanding through ever-tighter focus on particular terms and concepts. No subsequent writers will be able to avoid engagement with Powell's tenacious account of how this maps onto understandings of the crucial issue of church power, and to how those developed in the context of intense discussion between what John Morrill has described as “men under intolerable strain … striving to keep unity in the face of innumerable pressures” (Minutes and Papers of the Westminster Assembly, 1:ix).

There are, however, significant problems to set in the balance against these very real merits. Exceptional explanatory power is required to render both intelligible and interesting the demanding subject matter and immense detail of the discussion. Unfortunately Powell's prose is unhelpfully opaque. He is also simply too close to his sources: all but die-hard specialists in the period will often struggle to distinguish the wood from the trees—“signposting” and clarification are not Powell's strong suits. Like many authors of first books, Powell's relationship to much of the existing historiography is unnecessarily antagonistic, with a number of authors taken to task in unhelpfully aggressive style in order to magnify the novelty of his own work. Less tangibly but more generally, Powell's intense sympathy for the Apologists tends to lead to partial and critical assessments of other groups within the assembly and in the wider milieu, although partiality is often at the root of his critiques of other scholars. Nevertheless, Powell has written a book that those concerned with understanding the internal dynamics of the Puritan revolution will need to read, not least for his laudable concern to place the theological debates at Westminster into transatlantic and continental European contexts. Unfortunately, Manchester University Press has ended the practice of including a bibliography in the series. A return of that practice would both benefit this book and support best scholarly practices.