The interactions between religion and politics in the European integration process are the focus of increasing attention in political and academic debates. However, the body of research that has been developing for several years relates mainly to the representation of religious interests at the European Commission. The influence of religious actors and networks within the European Parliament give rise to many suppositions, ambitions or fears, but there are few empirical data available. To fill the gap has been the purpose of the international research project RelEP (Religion at the European Parliament) associating researchers from nine universities in Europe and beyond — findings of the RelEP project are presented in Religion and politics in the European Union, The Secular Canopy, Cambridge, 2014. Studying the normative preferences of European legislators reveals the conditions in which religion exerts an influence.