Evan Haefeli's Accidental Pluralism makes the striking argument that the rise of religious pluralism in Britain's American colonies was really a story of thwarted conformity, not precocious toleration. Few people in the early modern world, says Haefeli, valued religious pluralism (save the Ottomans and Mughals). Toleration, if early modern Europeans contemplated it, was supposed to be a temporary expedience designed to bring the wayward back to conformity, not a permanent state. Every colonial charter enjoined conformity with the prevailing religion in England. Rather than refuges, the colonies became extensions of England's religious politics. The problem was how those religious politics constantly shifted.

What Haefeli terms the “English world”—meaning more than just the Atlantic littoral to include places like Madras and Madagascar—was a battleground where Puritans, Laudians, Separatists, and Catholics sought to impose their religious visions. Casting a wide geographic net, including the failed as well as the successful English colonies, and sustaining a more or less rigorous chronology, Haefeli places America's religious pluralism in larger context.

One of the book's many strengths is how it weaves together metropolitan and colonial historiographies, making it appealing to a range of scholarly audiences. Such connections are central to the book's arguments, for metropolitan history drives change over time in Haefeli's account. Comparison to the Spanish Empire is not developed or sustained but is implicit throughout. Faced with an even more daunting geographic and demographic scope, the Spanish Empire succeeded, writes Haefeli, in imposing religious uniformity—despite evidence of local diversity. What explains colonial British America's pluralism was those colonies’ attachment to England. Lest one think that Haefeli is replacing “American exceptionalism” with an English variety, the seventeenth-century England at the center is more the “failed state” of Clare Jackson's 2021 Devil-Land than something out of Whig history. For Haefeli, what explains the rise of pluralism is historical contingency: dynastic changes and succession politics; the vagaries of royal patronage; the circumstances of individual colonies, especially the personnel in charge on the ground; and the personalities and policies of monarchs, notably James I and Charles I. Thanks to their juggling—the one seeking balance in a big-tent Church of England, the other making policy through favorites—pluralism practically snuck into the colonies (136).

The book's perspective is from the center out, and often from the top down. We see the issue of religious pluralism usually from the eyes of monarchs, courtiers, and colonial governors. The Quakers, for instance, appear largely as elites saw them: a nuisance challenging the outer bounds of what was, by then, the nebulous “church system” of the Protectorate (287). The other side—that is, the appeal of groups that rejected not just conformity but orthodoxy and hierarchy of all kinds, netting converts including John Winthrop's son Samuel—is not always as clear, and does not factor as much in Haefeli's explanation for the rise of pluralism.

Haefeli's book contains instructive paradoxes. Pluralism emerges because of efforts to achieve uniformity and conformity. Given the chance, every colony in the English world pursued its own form of religious conformity. Another paradox arises as English expansion—often in the name of conformist religion—leads to greater religious diversity. Enslaved Africans and Native Americans, in the beginning at least, are important factors if not entirely players in Haefeli's story. Both represented examples of de facto tolerance, he argues. The case of sovereign Native nations, as an example, is complicated and extends beyond Haefeli's examples of grudging New England Puritans (32) or the logic of colonial exploitation (302). Religious liberty was something that Indigenous peoples valued and defended. Notably in Virginia, Natives in tributary relationships maintained their religions in this era, resisting conversion. Well into the eighteenth century, many Native peoples held missionaries at bay, even shifting alliances to do so, especially in the Southeast.

Haefeli's finish in 1662 when episcopacy, uniformity, and persecution returned seems hardly the endpoint to this story. Even after 1688–89, the fight continued in England with its resurgent Church and in the colonies—notably the Carolinas. But the terms of the struggle did change and, for Haefeli, the damage to a pristine religious unity was irreparable long before then, whether the actors at the time realized it or not.