In his Religious movements in the Middle Ages, the German historian Herbert Grundmann established a new paradigm for the study of medieval Christianity. Whereas earlier scholars had focused for the most part on outstanding individuals or the history of particular institutions, Grundmann sought rather to draw out the common threads within twelfth- and thirteenth-century religion. At root, he argued, all medieval religious movements were expressions of a single idea: living the apostolic life.

The present volume has its genesis in an international conference held in 2015 to mark the eightieth anniversary of the publication of Grundmann's work and to assess its continuing influence. In their introduction, the editors highlight the aspect of Grundmann's legacy that has proved most problematic: his assertion that ‘[a]ll religious movements of the Middle Ages achieved realization either in religious orders or in heretical sects’. In reality, they argue, medieval religion was much more dynamic than this bipolar model implies. The purpose of the eleven essays presented here is thus to ‘develop a new narrative’ (p. 7) that moves beyond Grundmann and illuminates the space ‘in between the twin poles of “orders” and “heresy”’.

Letha Böhringer sets the scene with a discussion of Grundmann's relationship with the German Protestant Church and the NSDAP during the 1930s. She places particular emphasis on his decision to leave the Protestant Church in 1934, which seems to have been motivated not by any deep-seated ideological commitment to Nazism on Grundmann's part but by a more generalised distaste for institutional religion. In her essay, Sita Steckel looks at how the charge of hypocrisy was deployed by clerics against their theological opponents from the eleventh century onwards. Taking her cue from Grundmann, Steckel argues that traditional periodisation – specifically, the ‘historiographical watershed’ between the high and late Middle Ages – is unhelpful when it comes to understanding this phenomenon, as there is significant continuity between the critiques articulated during the eleventh and twelfth centuries and late medieval ‘anti-fraternalism’. Other contributors highlight some of the limitations of Grundmann's approach. Amanda Power acknowledges Grundmann's role in shifting the focus away from St Francis and other prominent individuals towards the broader religious context from which they emerged, but notes that ‘he did not sufficiently challenge some of the core assumptions’ (p. 62) of those working in the field. What is now required, Power argues, is a critical reappraisal of the ‘self-evidently virtuous category’ (p. 63) of apostolic spirituality itself. Neslihan Şenocak is similarly critical of Grundmann's understanding of the vita apostolica. In its place she proposes the broader concept of ‘associative religiosity’, which acknowledges the role played by lay organisations such as confraternities and is more reflective of the corporate nature of medieval institutions. Anne E. Lester's essay sheds light on another facet of medieval religion largely ignored by Grundmann: crusading and the forms of piety that it engendered. Through an examination of the career of one prominent female crusader, Mahaut of Courtenay, Lester makes the case that crusade devotion constituted a religious movement in Grundmann's terms. This movement of ‘vernacular crusading’ found expression in a variety of forms, including patronage, works of charity and new literary genres.

One of Grundmann's most notable contributions was his pioneering work on what he called the women's religious movement. Famously, he posited a link between the emergence of female religious communities and the development of religious literature in the vernacular, a thesis explored further here by Sean L. Field. Whereas Grundmann argued that this literature arose from the interaction of religious women with male mendicants, whose translations inspired them to compose their own works, Field suggests that the picture was more complex. Some women became writers outside a mendicant context, while many texts dealt with issues of institutional identity, rather than the mystical themes emphasised by Grundmann. In her contribution, Janine Larmon Peterson addresses the question of why female heretics were rarely designated as ‘heresiarchs’ during the Middle Ages. This was not, she contends, because women did not hold leadership positions within heretical groups but because in practice the term tended to be reserved for ‘those who challenged the political, rather than the religious, power of the papacy’ (p. 274). A more conventional model of female spirituality is provided by the Roman noblewoman Margherita Colonna. According to Lezlie Knox, Margherita's career offers a window on to the women's religious movement in thirteenth-century Rome, which was characterised by active piety and not yet fully confined to monastic institutions. Another group of religious women ‘on the fringes’ were the so-called Grey Sisters, whose history is reconstructed by Alison More. Despite various attempts over the centuries to regularise the sisters’ status, the ambiguity of their position as unenclosed nuns engaged in charitable work was never fully resolved. The same applies to the communities of semi-religious women known as beguines. Although the beguines were condemned at the Council of Vienne, Tanya Stabler Miller shows that the Church was by no means uniformly hostile to such women. For the secular priest Robert of Sorbon, the ‘in-betweenness’ of the beguine lifestyle represented not a threat but ‘an alternative conception of religious community’ (p. 222) beyond the cloister, the ordo caritatis. Robert and his students forged close relationships with beguine houses in Paris and elsewhere, which became a key part of the Sorbonne's pastoral outreach. Late medieval Prague, too, was home to numerous beguine communities. As Jana Grollová shows, beguines were prominent among the supporters of Jan Hus in the early fifteenth century, as well as a key target audience for the devotional literature in Czech that was emerging around this time.

This is a wide-ranging but focused collection showcasing work by some leading scholars in the field. The volume both builds on and offers a useful corrective to Grundmann's study, illustrating the diversity and ‘messiness’ (p. xviii) of medieval religious life and suggesting possible directions for future research.