Deep research and conceptual sophistication make Mark Valeri's Opening of the Protestant Mind a landmark account of a discursive “before” and “after” in the English/British homeland and its colonies during the early modern era (England became Britain after the 1707 Union of English and Scottish monarchies). In the “before” period, the political–social–religious chaos of the English civil wars (1640–60) stimulated a reaction that reaffirmed religion as integral to “confessional order” (3), the instinctive understanding of national allegiance and Protestant faith as a unified whole. English observers of the world in the years following the Restoration of the monarchy (1660), thus, viewed Roman Catholicism as “completely antithetical to all things English” (17), they “constructed relentlessly pejorative accounts of non-Protestant religions” (21), and they described conversion as conformity to the Protestant regime.

“After” the peaceful replacement of James II by William and Mary in the “Glorious Revolution” of 1688–89 and the accompanying Edict of Toleration, attitudes changed. Valeri documents these changes in well-known figures like Cotton Mather, Jonathan Edwards, and the British political thinkers Thomas Gordon and John Trenchard, but also from a wide variety of publications that, whatever their popularity then, have been little noticed in conventional histories of the period. They include diplomatic reports, fugitive publications like broadsides and playing cards, sermons by obscure clergymen, and reference works like William Turner's History of All Religions in the World (1695), Jeremy Collier's edition of Geographical, Genealogical, and Poetical Dictionary (1701), and Thomas Broughton's Historical Dictionary of All Religions from the Creation of the World to the Present Time (1742). Especially important for charting the altered conceptual landscape are widely read travel reports by the likes of the Anglican bishop Gilbert Burnet and the young American merchant Jonathan Belcher on Christian Europe (1680s, early eighteenth century, respectively), Lady Mary Wortley Montagu beyond Christian Europe (1710s), the sailor William Pote, Jr. through French and Indian North America (1740s), and the Maryland physician Alexander Hamilton among Indigenous Americans (1740s).

In these sources Valeri finds descriptive rather than prescriptive accounts of intra-Protestant and Protestant-Catholic differences, strikingly relaxed attitudes toward non-Christian religions, and approval of religious liberty depicted as the exercise of reason and voluntary choice. In his words, “Allied with the crown after 1688, [British Protestants] expanded the meaning of toleration and linked it to what they regarded as other social virtues such as reasonableness and civility” with the result that “the Anglo-Protestant discourse of religion and politics and of the religious ‘other’ in 1700 bore slight resemblance to the discourse prior the revolution” (70).

A comparison concerning the evangelization of Native Americans offers one of the most compelling examples of these changes. The efforts of John Eliot among the Algonquian during the last third of the seventeenth century and David Brainerd among the Susquehannock and Lenape in the middle third of the eighteenth do reveal commonalities of zeal, dedication, and a willingness to practice what most of their fellow-Protestants only preached. But the contrast is also sharp.

For Eliot, the conversion of American Natives required first their civilization. Authentic Indigenous Christianity meant gathering “praying Indians” into model English towns and having them come to think like English Protestants. In the next century, Brainerd considered Native moral consciousness perfectly adaptable to the faith. In fact, he could critique the conduct of British colonials by comparing it unfavorably to the morality witnessed among Indigenous people. His evangelistic appeal to the Natives, but also to the European settlers of the middle colonies, asked them to “set aside their familial, tribal, or political identifies and embrace the gospel as unencumbered, reasoning individuals” (170).

At first glance, it might seem difficult to include Jonathan Edwards, the editor of Brainerd's much-read diary, among those who left behind “confessional” assumptions. Wasn't he the last of the Puritans, with notably conservative views about social order and militant certainty about predestinarian Calvinism? The book's answer is, “yes, but . . .” While Edwards did maintain traditional theological conclusions, Valeri shows that as Brainerd's editor he emphasized the missionary's “rational and just” (168) approach to evangelization. As preacher to the Stockbridge Natives late in his career, he echoed Brainerd's benign view of Indigenous moral consciousness. In his treatise, The Nature of True Virtue, he went part-way with Francis Hutcheson's definition of benevolence. He viewed France and Spain as the antichrist, not because as Catholic powers they embraced the errors of Catholic theology, but because as wagers of unjust war they exemplified the papacy's abuse of power. And he described human freedom in his noteworthy treatise on that subject as the power to do what one wanted to do, an account with no preference for anything British or Protestant but that instead reflected “the moral, philosophical, and political mandate to assert the moral competence and freedom of all people” (177).

Valeri records similar movement beyond “confessionalism” in many others. Cotton Mather praised his father Increase for speaking up for religious toleration. Jonathan Mayhew fulminated against Roman Catholicism because “papists” relied on coercion instead of appeals to moral consciousness. At the end of the eighteenth-century Hannah Adams became particularly noteworthy for her pioneering, but also dispassionate treatment of world religions.

The success of The Opening of the Protestant Mind depends upon Valeri's nuanced account of “discourse,” or instincts, assumptions, and taken-for-granted habits of mind. He recognizes that deference to certain instincts of the ancien regime did not vanish entirely, also that eighteenth century's standards of reasonableness could be employed to justify the enslavement of Africans and the extermination of Natives. Moderate Protestants did often support the presumptions of colonial settlement. He also knows that the eighteenth century's relatively dispassionate accounts of non-Christian religions entailed a secularizing tendency that would blossom into nineteenth-century accounts of religion as strictly social, anthropological, or psychological.

Yet through extensive documentation of the actual thinking of real Protestants he has shown that – along with the era's other important economic, political, and cultural forces – Protestant minds were opening, and that this opening began with the peaceful regime change of 1688.