Simon Ditchfield gained his PhD from the Warburg Institute at the University of London, UK in 1991. Since then he has held a variety of positions in the Department of History at the University of York, UK. In 2014 he became Professor of History there and has been working on writing a history of the making of Roman Catholicism as a world religion in the period 1500–1700 ca. For the POLY project he gave a lecture in May 2021 on Agency and Appropriation in Early Modern Roman Catholicism and in July 2022 on Rome Calling? Rewriting the Catholic Reformation for the 21st Century.