The numerous occasions on which French and Italian conceptions of Catholicism clashed in the course of the sixteenth and the beginning of the seventeenth centuries are the subject of this edited collection. With a few exceptions, the majority of the articles are written from a French perspective, and rightly so given the central place of the French Wars of Religion in the successive crises of Catholic orthodoxy. Pre-Reformation controversies and the difficulties that the freedom of the Gallican Church caused French ecclesiastics and lawyers in their relationship with Rome are also given their due, notably in the essays by Frédéric Gabriel and Benoît Schmitz. But the majority of the essays concern the crisis that shook the French monarchy in the wake of the Holy Catholic League in its appeal to Roman orthodoxy against a certain conception of the state that was promoted by the Politiques. But the essays consistently challenge the historiography of state building that placed Rome as an obstacle to be overcome so that the modern state could emerge. Rather Rome is described as a partner with which theologians, magistrates and ambassadors were in dialogue and in which the respective contributions of each party to the other's political and ecclesiastical conceptions were relatively balanced.

Sylvie Daubresse, for instance, argues that the parlement of Paris's exclusive legal interpretation of the liberties of the Gallican Church allowed some crises to be defused and that beyond a partisan body, the parlement served as a buffer between the king and the pope. One of the staples of Gallicanism, for instance, its frequent resort to conciliarism to question the authority of the pope in church councils, was short-circuited by the advent of the Protestant Reformation that allowed Rome to respond with the accusation of heterodoxy. This is a clear instance in which heterodoxy was brandished as an argument in what could be argued was a purely political or diplomatic controversy, but as Schmitz demonstrates in his discussion the Council of Pisa in 1511, it predated the Protestant Reformation. If the Reformation rendered the relationship between the Gallican Church and Rome even more complex, it is also because the Italian and the French Churches were at loggerheads about how to deal with the Protestant heresy. Michela Catto's essay on catechisms is a case in point, showing how the catechisms written ahead of the Council of Trent, by Augier and Canisius in France and the Empire respectively, contravened Tridentine injunctions against engaging with the Protestant heresy directly, but were perhaps more effective than the Tridentine equivalent. In a similar vein, the collection devotes a number of chapters to the question of censorship (by Gigliola Fragnito, Jean-Louis Quantin and Giorgio Caravale) in which religion and politics played an equal part. Jean-Louis Quantin, for instance, notes that the universal ambitions of the Roman Index were thwarted by national initiatives, notably in France, where censorship was gradually wrested away from the control of the parlement and the University of Paris in favour of the monarchy.

But the relationship between France and Italy was never so fraught as during the crisis of succession of 1584 when Henri iii declared the Protestant Henri of Navarre as his legitimate successor, which is the focus of the lion's share of the essays. Just as Daubresse argued that the parlement acted as much to defuse as to create conflict, Barbiche demonstrates, through a careful analysis of diplomatic correspondence between Paris and Rome during Henri iv’s reign, that strategies were in place to avoid direct confrontation. Elena Valeri, for her part, has analysed the Italian histories of the French Wars of Religion and concluded that Rome was not as much a partisan of a Spanish takeover of the French crown as the Politiques made it out to be. The complex interplay between diplomacy, politics and religion is explored further in a number of essays that discuss French and Italian responses to printed polemic and its condemnation by the papacy. Jean-Louis Quantin, for instance, demonstrates that the placing on the Index of forbidden books of the anti-papal polemic that was produced by erudite Gallicans was interpreted as little more than a posture and effectively ignored across the Alps. Benoît Schmitz notes a similar phenomenon in reverse in Rome's attitude towards the Politiques’ responses to the papal bulls that excommunicated Henri iii and Henri iv. Jean-Pascal Gay, in his analysis of Chichon's controversy with the Jesuits at the beginning of the seventeenth century, comes to a similar conclusion: one should differentiate between the formal posturing of the respective parties and their genuine political intentions or aims. The three essays on Venice that conclude the collection come almost as an afterthought, which is surprising given its importance in the debate between Paris and Rome.

The idea summarised in the title of the collection – ‘crossing heterodoxies’ and ‘plural Catholicisms’ – follows in the footsteps of the considerable contribution to historiography made by Thierry Wanegffelen and Alain Tallon in the 1990s in their respective works Ni Rome ni Genève and La France et le Concile de Trente. Since these works were published it is no longer possible to argue that heterodoxy was subsumed to Protestantism, on the one hand, and that Catholicism was monolithic, on the other. As many of the essays included in this collection argue, heterodoxy was a fluid and malleable category that could be applied equally by one side or the other given the specific context in which it was evoked. But the collection goes beyond theological considerations and demonstrates once more, if it were at all necessary, that in this period religion and politics were indissociable and in some cases indistinguishable from one another. This collection gathers together an impressive array of specialist essays in their respective fields which together amount to a valuable addition to the scholarship on ultramontane relations.