The volume Enlightened Religion. From Confessional Churches to Polite Piety in the Dutch Republic, edited by Joke Spaans and Jetze Touber, is based on one of Ernst Troeltsch’s ‘hunches’ that in the decades around 1700 Protestantism was redefined and reconceptualized. Moving away from its earlier confessional variant that had emerged over the course of the sixteenth century, this new or modern Protestantism gradually evolved into a ‘personal conviction for its adherents’ (1). This larger and overarching development is outlined in a clear and useful introduction, after which twelve individual contributions reflect on a variety of developments that contributed to the modification of Protestantism in the late seventeenth and early eighteenth centuries.

Except for Martin Gierl’s essay on the Pietist controversies in the Holy Roman Empire (and Brandenburg in particular), all the contributions focus on developments in the Dutch Republic and, in one case, its overseas territories. Divided into two parts, five contributions zoom in on larger intellectual trends which fostered the reconceptualization of Protestantism, whereas the others comprise case studies of intellectuals – including ‘second tier’ ones such as Willem Goeree, Arnold Houbraken, and Johannes Duijkerius – whose work and output provide concrete examples of changing ideas about religion, its place in society, its relation to the secular government, and other themes. Henri Krop’s contribution has the widest scope: by surveying the work and ideas of several theologians and philosophers from different religious backgrounds, he shows the transition from the idea that there is one, true religion, to the notion that there are several religions, all of which might be ‘true’ as long as they contributed to the moral perfection of man and society. This suggests a shifting focus, away from issues pertaining to doctrine to morality.

Another conceptual shift, related to the idea of the providential history of the world, is traced and studied by Jetze Touber. Based on the voluminous correspondence of the magistrate and antiquarian Gijsbert Cuper, Touber shows how earlier ideas about the divine origin of alphabetic scripts were slowly but surely undercut by the discovery of human scripts from different parts of the world. This spurred intellectual creativity and confusion – such discoveries could point at the truthfulness of radical theological ideas including La Preyère’s pre-Adamite thesis – and, in general, evoked scepticism about the ‘teleology of providential world history’ (103). In other words, the theological and intellectual framework which had accompanied the confessional type of (post-)Reformation Protestantism was challenged and tested by new scientific discoveries and ideas.

Other contributions elucidate particular aspects of the process of transformation that Protestantism underwent. These include the changing genres and media in which discussions were waged and information was presented, the various circles in which recent and relevant literature was discussed, the involvement of a range of people who are not readily associated with the Enlightenment discussions on religion, and the different conceptions of religion in the work of, for instance, Romeyn de Hooghe and Marcus Zuerius Boxhoorn. Taken together, the chapters offer a wide pallet of factors which underpinned the reconceptualization of Protestantism. Helpfully, the introduction highlights a number of common themes which run through the individual contributions (14-17). Particularly insightful is the observation that while the ‘content of religious doctrine and practice’ often remained intact, the attitude to other religions changed: to an increasing extent, people agreed to disagree. This, however, is not to say that the content of religious belief and practice continued to be set in stone. Indeed, the knowledge generated by scientific progress, new world discovery, and critical scholarship, among other endeavours, could force people to reflect on religious truths and religion more widely and be a motor of change. As a result, new information about historical alphabets – to mention but one example – could inspire a more critical stance towards a history of mankind that was derived from and based on the Bible.

Given the many intellectual developments, including the continuing relevance of the humanistic legacy with its emphasis on the importance of philology, the flow of information which resulted from an increasingly connected and globalized world, and the growing influence of (early) Enlightenment thought, that converged in this reconceptualization of Protestantism, the editors’ clarion call for a ‘new, more interdisciplinary type of the history of religion’ (9) is very much legitimate. The contributions amassed in this volume do succeed in the aim expressed by the editors, namely ‘pointing to fruitful lines of approach for further research’. Through the inclusion of ‘second tier’ intellectuals, a variety of printed publications and genres, and developments in the media landscape and communication strategies, each of the contributions showcase how this reconceptualization of Protestantism can be studied and where it can be located. Still, it would have been helpful if some of the contributions could have been tied more closely to the volume’s overarching thesis; sometimes the particular ways in which a case study contributed to the emergence of a new type of Protestantism in the Republic could have been developed more fully.

Apart from succeeding in its stated goals, the volume also contributes to fields of research which do not squarely fall within its scope. Although the introduction mentions the desirability to link socio-cultural and intellectual history in the context of the Enlightenment, the volume’s contributions did not set out to do so. Still, in conjunction with other recent research, the volume alludes to the interaction between and entanglement of religious and Enlightenment thought. Apart from further undermining the idea that the Enlightenment was completely antithetical towards religion, the notion of a reconceptualization of Protestantism and the shift toward polite piety (which is also posited by other scholars working on the Dutch Republic) is a potentially profitable way to think about the relationships and interaction between members of different confessions. To what extent did the intellectual developments studied in this volume affect interconfessional relationships and how? Were other confessions and religions subjected to similar developments as well? The fact that this volume also stimulates scholarship undertaken in other, if aligned fields of research, bears witness to its quality and is the perfect example of the wide readership it deserves.