Serrano's talk focused on the way in which the phenomena of conversion and apostasy are dealt with in medieval legal texts.

During the Middle Ages, legal texts were used in the Christian kingdoms on the Iberian Peninsula as a means to promote the conversion of infidels and the persecution of Christian apostates. The aim was to uphold Christianity, the dominant religion, in the face of the heretic practices of Judaism and Islam.

A series of discriminatory and punitive legal measures introduced by various monarchs at the time played a role in reinforcing this movement, which received support from the ecclesiastical courts. The result was a peculiar symbiosis between kingdom and church.

However, it is worth noting that the Iberian Peninsula of the 12th and 13th centuries was home to a variety of different kingdoms, each containing its own distinct laws and unified only by a single external legal framework: the new Roman Canon. The upshot was that some kingdoms on the peninsula, such as Navarra, sought the conversion of infidels with less zeal, while others, such as Catalonia, Castile and Aragon, were far more repressive.

The workshop was organized by the Université de Nantes and the programme sought to shed light on the different legal approach to conversion in medieval societies.