This edited volume engages a long-standing religious power, the Holy See, to discuss the impact of the structural and postsecular transformations of international relations through the emergence of a global and digital public sphere. Despite the legal construction that enables the separation of the Holy See as a distinct legal entity, it is also an instrument for the papacy to represent externally and regulate internally the global and transnational Catholic Church. The Holy See is also the tool that enables the papacy to address a transnational or a global public beyond Catholic adherence - most prominently through journeys that are often at the same time state visits and pastoral journeys. Instead of understanding these hybrid roles as an irregular exemption, the contributions of the book argue that the Holy See should be seen as a certainly special but nevertheless quite normal actor of international and public diplomacy.