This chapter sketches the philological and codicological work on Gratian’s Decretum and how that work is being employed in new ways. It begins by briefly touching on the collection’s wider dissemination as a way of placing it within an overall context of the Corpus iuris canonici. It then sketches the contributions of Stephan Kuttner and Peter Landau followed by the Redaktionsgeschichte of the text. The role the Decretum played in the transmission and fluidity of legal knowledge is analyzed through the lens of two case studies: Gratian’s balancing of the spiritual and secular roles of the feudal bishop, first, and, second, a unique case found only in one manuscript.

Pope Gregory VII and his personal views as expressed in the Dictatus papae and his references to the forged “Donation of Constantine” opened the way for the debated papal monarchy of the twelfth century. The gradual reversal of the ancient Gelasian doctrine of the relationship between spiritual and worldly powers was achieved and furthered by division within the Salian dynasty and the general social evolution and feudalization of Western society. It was not a revolution. Against the background of the council of Sutri of 1046, when Emperor Henry III arranged for the settlement of disputed papal elections, this chapter focuses on the internal changes – especially since the time of Leo IX (d.1054) – leading to a reformed papacy prior to Gregory VII (including monastic and clerical renewal as well as eventually organizational changes within the Church, such as, in no particular order: the College of Cardinals, the use of legates, the use of privileges, revival of ancient canon law, a camera along the pattern of Cluny, oaths of obedience, etc.). These changes enabled the papacy to challenge in particular the claims to sacrality first of all by the Salian monarchy but eventually of all monarchies.

Saxony, home of Martin Luther, was the first country to be divided over the issue of the Protestant faith. While Ernestine Saxony became the heartland of the Reformation, the neighbouring principality of Albertine Saxony saw the beginnings of the Counter-Reformation. The two Saxonies provide almost perfect laboratory conditions for comparing contrary reactions to the Reformation. By investigating the lives, piety and politics of the Wettin princes, Frederick the Wise, John the Constant and George of Saxony the Reformation is revealed to have been a true game changer. Christian humanism, attempts at church reform and sympathy for the Reformation did not correlate neatly. Rather, the dynamics of religious conversion disrupted lines of continuity from the Middle Ages into the early modern era. That disruption testifies to the groundbreaking impact of Protestant ideas. At the same time, early resistance to Luther in Electoral Saxony proves that even in his homeland, Reformation and Catholic reform were alternatives right from the very beginning.

This chapter provides an interpretative framework for understanding the remarkable regeneration in Catholic thought in the first half of the twentieth century that inspired a renaissance in theology and liturgy, patristics and biblical studies, and contributed decisively to the pivotal reforms of Vatican II. The chapter is in three parts and considers, first, the emergence and development of a threefold stream of renewal at the center of ressourcement; second, the distinctive contribution of the leading Jesuit and Dominican pioneers of ressourcement to theological renewal, the churches, and society; and third, the transformation of Nouvelle Théologie into a universal program of reform.

The twelfth-century abbot Joachim of Fiore numbers among the most important and influential Christian apocalyptic writers of the Middle Ages. This chapter explores the contours of Joachim’s ideas about the patterns of history, situating him and his works within the broader apocalyptic “revivalism” of the twelfth century.