POCRAM is a research project concerning the various attitudes and positions of the political power to religious conversion. It belongs to the sub-theme “Religions et systèmes mythiques” of the Call for Projects program, more specifically connected to “questions of religious transfers” and “relationships between religion and the definition of a nation”. State coercion in religious matters is a hot topic, which often inspires simplistic discourses opposing tolerance and bigotry. Our approach of interplays of political powers and religion is both open minded and focused on historical situations located in a distant past, when an impressive variety of attitudes to conversion were elaborated. All religions require from their followers recognizable signs of membership, organized in more or less complex and more or less binding systems; these systems, which have been codified across history, make religious changes visible to political authorities, and eventually sensitive to them. We shall work on religious conversions as much as they can be perceived through such signs. This is why we shall focus on individuals or groups of people changing their adhesion to a religious association, leaving apart the study of conversion as a personal experiment of intellectual or spiritual metamorphosis. By religion, we mean any organized structure based on a specific view of the world and a system of belief. By political power, we mean any form of civic authority or organization, whatever its scale. Interplays of political powers and religious conversions can happen in many various ways: political power can identify itself with a religious group, collaborate closely with it, as well as it can disqualify it, or confront it. Political attitudes vary according to a complex set of factors depending on the position of religion in human society, on the flow of converted people, on the political and ideological background. However, despite a large number of publications on religious conversion as such, no global study of political interferences exists. A significant number of studies devoted to local situations suggest that the time has come for such a global research project. We believe that studying the various political attitudes to conversion, seen as a sign of religious changes, can be a privileged way to a better understanding of the situation of religion in any society. We aim to study these attitudes in different settings ranging from the end of Antiquity to the ‘critical years of the European mind’ at the end of the 17th century. Our starting point is Western Europe and relationships between Christianity (in its many branches) and other religions (Judaism, classic Mediterranean cults, Islam, as well as extra-European religions met by Christianity), and relationships between various branches of Christianity. At some point in the project, scholars working in different cultural fields will be invited to help to see European contexts in perspective. Our goal is to elaborate a typology of political attitudes to religious conversion, to build up conceptual tools, which could be used by historians to study religious conversion as a key element of religious change. We shall use a comparatist approach, considering specific case studies across time and contexts. The research project is historical at heart, processing situations across a long period of time and a wide geographical area, but dialog with political science, sociology and anthropology is an intrinsic part of it.