The relationship of the Grand Dukes of Tuscany with the ecclesiastical hierarchy was not always a happy one. Cosimo i de’ Medici (r. 1537–74) clashed with the archbishops of both Florence and Pisa over the expansion of Medici power and, moreover, was cautious about allowing the Inquisition access to his territories. The rise of the Jesuits added a new dynamic, and Kathleen Comerford's book takes as its subject the contacts between the new Medici grand-ducal state, effective from 1532, and the Society of Jesus, recognised by the papacy in 1540, which were characterised by co-operation on the one hand and tension on the other. Her detailed archival study of the establishment and development of the Jesuit colleges in Florence, Siena and Montepulciano is supported by two chapters considering the rise of the Medici Grand Dukes. Jesuit education, Comerford argues, served early modern rulers well because of its focus on training a ‘moral and active populace’ (p. 5); the Society might also be a bulwark against heresy. From the Grand Dukes’ point of view, religious innovation was a threat to political order, and while at times this played in the Jesuits’ favour, it might also work against them, as in the 1540s when there remained concerns in Florence about a revival of Savonarolism (it was only later that the Medici decided to co-opt its legacy).

While the Jesuits’ Spanish connections often proved contentious in Rome, in Florence they dovetailed with those of the ruling family. The Medici had returned to power in 1530 with the backing of the Holy Roman Emperor, Charles v and his Spanish troops. Cosimo i had married Eleonora di Toledo, daughter of the Spanish Viceroy of Naples, and her influence was significant in enabling the Jesuits to gain support for their early Tuscan projects, including the foundation of a college in Florence. After lengthy negotiations about a suitable location for the college, in 1552 the Jesuits moved to the Ospedale di Santa Maria Nuova. Five years later they had 120 day students, but numbers were volatile and fell to thirty in autumn 1558, although this year did see one of the Medici sons, either Garzia or Ferdinando, in attendance. As a consequence of understaffing, the college's first years were difficult, and Eleonora's death in 1562 deprived it of significant patronage, leaving it in financial trouble. Comerford's study makes clear the importance of the Grand Duchesses, and in particular the Imperial brides Giovanna d'Austria (wife of Francesco i) and Maria Maddalena (wife of Cosimo ii), in supporting Jesuit initiatives; the significance of both gender and imperial connections might have been drawn out further. In contrast, neither Bianca Cappello (Francesco's second wife) nor Cristina di Lorena (who married Ferdinando) took a major interest although Cristina's interest grew somewhat after her husband's death. Other female donors played important roles too.

In Siena the Medici and Jesuits had parallel interests in stamping out heresy after the city's conquest, but there was public controversy between local ‘heretics’ and the Jesuits, the former accusing the latter of sexual misconduct and spying. Like the Florentine Jesuits, the Sienese suffered financial challenges; again it took some years before suitable accommodation could be found and developed; Jesuit involvement in a campaign against rumoured heresy at the University of Siena also created conflict with locals. The Montepulciano college had more difficulties still, to the point that the Society withdrew formal support. Activity only revived after the turn of the century, when the assistance of the Grand Duchess Maria Maddalena was significant. By the turn of the sixteenth and seventeenth centuries, however, the colleges in Florence and Siena were flourishing. They were also international. Comerford's prosopographical study of the residents shows that in February 1556 the fourteen Jesuits resident at the College in Florence included men from Bohemia, Spain, the Holy Roman Empire, Milan, Ferrara, Florence and Montalcino (near Siena). This stood in contrast to priests in the local diocese, who were far more likely to be Tuscan in origin.

Comerford concludes that the Society of Jesus and the Medici worked together to create ‘more centralized communities, with citizens better schooled in the Catholic faith, than had existed before 1532’ (p. 215). Yet behind this narrative of successful partnership the archives reveal some notable periods of neglect on the part of the Medici, who were certainly not consistent or reliable patrons. If, on balance, the Grand Dukes and the Society were indeed mutually dependent the relationship was not always a comfortable one. This book makes admirably clear the nuances and challenges of the Church–State relationship in early modern Europe.