Christian Mühling's aim in this commendable book is to explain a certain phenomenon, namely, the crystallisation of the notion of ‘war of religion’ in the late seventeenth/early eighteenth century and how it internationalised. Mühling extensively details the case studies of France, the Holy Roman Empire and England and focuses on these decades because it was then, a generation after the 1648 Peace of Westphalia, that a wide debate concerning ‘war of religion’ first occurred and that the notion solidified as a political buzzword. It also emerged as an indicator of a certain era in the past – specifically, historical writing and research began projecting it, anachronistically, back onto the age of confessional disputes of the sixteenth/early seventeenth century. The essential attribution, that religion was responsible or, at minimum, played a substantial role in the wars which occurred during that time steadily formed into the notion of war of religion. Among the last of these wars were the Thirty Years War (1618–48) in the Holy Roman Empire, and the Civil Wars (1642–51) in England. In the centuries after the debate emerged, scholars from a variety of schools of thought regularly employed the notion and made it a mainstay in scholarly discourse.

Because the medium for the debate was dailies (pamphlets, newspapers, periodicals) and books, and because their publication surged toward the end of the seventeenth century, the debate transcended regions and boundaries. German, French- and English-language sources took centre stage because the central confessional disputes played out in those regions. While the notion was already being talked about during the Thirty Years War, discussion of it quieted after 1648, and then revved up again at the beginning of the 1680s. In France, the debate originated between Catholic clergy and Huguenot pastors over the historical legitimacy of the 1598 Edict of Nantes. The debate then became greatly Europeanised via the Huguenot diaspora. Memorials concerning the French war of religion were received and adapted in Germany, and, from there, both French and German memorials gained entry in the British Isles. Indeed, the European book market made sure that the debate spread to almost every corner of the continent.

Catholic and Protestant clergy were the ones who essentially developed and maintained the debate, and their publications reached an audience of literate elites who engaged in it. In Catholic publications a war of religion was synonymous with a crusade against heresy, and therefore the wars surrounding confession that were waged against Protestantism were likened to medieval crusades against the Albigensians and Waldensians. Whereas Catholic clerics routinely accused the Protestants of having instigated the wars of religion, Protestant publications couched them as ones in which Protestants had to tread between being faithful subjects and defending their own faith. Protestant pastors denied accusations that Protestants had led any of the wars. For example, Lutheran historical writing pitched Martin Luther as an apostle of peace who, like his successors, disapproved of a war of religion between the confessions. Protestant authors faulted instead a fanatical Catholic clergy, especially the Jesuits, for having carried out the directives of the papacy, and zealous Catholic sovereigns. Protestants in the Empire, France and the British Isles were, therefore, justified in their resistance. In sum, Catholic memorials developed a thoroughly positive relationship to wars of religion, while Protestant journalism regarded them negatively as a defence against opponents.

Both sides legitimised self-defence. Both also viewed the opponent as a danger to their own community, having a rebellious character and being incapable of waging a true war of religion. Only the Catholic side, above all in France, entertained an offensive war of religion in order to purge heresy. Otherwise, a majority of authors on both sides tended to lean away from the idea. On the whole, Mühling would revise a thesis current in the writing of church history, i.e. that the clergy scarcely took part in the debate over war of religion. The debate, Mühling argues, was in fact led by them in dailies and in the historiography. It was so above all by theologians who often served temporal authority. Clerics’ words indeed had an impact on political powers.

Similarly, Mühling finds problematic the widely spread thesis that confession diminished as a factor in international relations after 1648. Instead, Mühling states that confessionalisation reached a second high point in the public debate which swirled in the late seventeenth/early eighteenth century, a full generation after the purported end of the so-called age of confessionalisation. After the Revocation of the Edict of Nantes (1685) and the Peace of Westphalia, Mühling states, political language became deeply informed by the debate over war of religion and also by confession. Counterintuitively, that is, people were more – not less – affected by ‘confessional socialization and confessional patterns of behavior’ than before. Mühling asserts this argument directly against an idea advanced by Heinz Schilling in recent decades, namely, that confessionalisation led to a secularisation. Following this line of thinking, Mühling contends that the propagation and condemnation of a war of religion during the age of Louis xiv was no sign of secularisation. Rather, it was much more a component of a deep confessional-religious worldview, one which had been instituted following the first stage of confessionalisation in the sixteenth and seventeenth centuries.

I suspect a certain other phenomenon would assist in explaining the one explored in Mühling's book. In the Empire, at least, the world of Christian monism, which confessionalism tried to articulate in creedal form, yielded to a world of Christian pluralism at the signing of the Peace of Westphalia. Consequently, and in contrast to what standard histories have led one to assume, the terms Catholic, Lutheran and Reformed, which previously had been hotly contested or disputed by adherents of the confessional parties, became naturalised and categorised as denominational descriptors in the Empire. The term Protestant underwent similar transformation. As a result, politics and religion steadily disaggregated on multiple levels across the Empire, causing religion to separate as a more distinct category and undergo a change in meaning and usage. Furthermore, rival parish networks began overlapping in towns and villages, giving the clergy, key figures in Mühling's study, newfound animus against their adversarial counterparts. Crucially, they, along with authors of history, engaged in another kind of anachronism – projecting the categorised descriptors back onto pre-1648 history and the writing of it. The time frame of these developments coincides strongly with the ones in Mühling's study. The aggregate portrait indicates that religion and confession exerted much greater influence on the historical process in the decades around 1700 than conventional scholarship has allowed.