The editors of this book met in 1991 in the Middle Ages study group led by Christian Krötzl, who was then a doctoral student at the University of Tampere. He defended his dissertation Pilger, Mirakel un Alltag. Formen des Verhaltens im Skandinavischen Mittelalter in 1994. Christian and the study group made excursions to Rome, Paris, and Tallinn, not to mention various domestic sites of interest to medievalists. Supplementing the more official program, we also had epoch fests and gatherings in more contemporaneous themes. As a post-doctoral researcher, head of the Finnish Institute in Rome (2000-2003), head of several projects of the Academy of Finland, and as a professor in Tampere (from 2005), Christian Krötzl has successfully created an atmosphere of support and encouragement, inspiring his students to aim high.

At the University of Tampere, Christian Krötzl is a key figure in establishing the conference series Passages from Antiquity to the Middle Ages (from 2003) and forming the Trivium – Centre for Classical, Medieval and Early Modern Studies (first a network in 2006 and since 2015 an official research centre). The Middle Ages study group also still vigourously cultivates future medievalists; several of the former members have now defended their doctoral dissertations.

While championing the colloquial approach, Christian Krötzl is a standard-bearer in the field of Finnish academia in other aspects. In the 1990s, he embraced a profoundly international approach at a time when internationality was not yet the norm in Finland. Indeed, one of his most important roles has been to introduce his students to foreign experts, thereby creating many fruitful relationships. International collaboration ranks high among the values Christian teaches his students, requiring, for example, reading skills in the major European languages (and sometimes in the minor ones as well).

As the following essays demonstrate, Christian Krötzl's range of interests is large and varied, from hagiography, everyday life, and lived religion via the papal curia and administration, to crusades and conversion in the Baltic Sea Region. The editors of this volume have also chosen different paths, one an expert in papal administration and justice, the other a specialist in hagiography and lived religion.