The Eastern shores of the Baltic Sea have always been a borderland region between the influences of different political, cultural and religious worldviews. In the early modern period, this was especially visible in the wars between Orthodox Russians, Catholic Poles and Lutheran Swedes. This research project wants to conceptualise the manifold relations between the different religious communities in the area known as Polish Livonia in the period from 1621 to 1772. In order to focus on the contact between the various groups, it will focus on the negotiation of boundaries and politics of recognition. The negotiation of boundaries between the confessions means establishing a canon of ‘tradition’ which is then dissimilated through various media. In the early modern period, this includes petitions to the authorities, episcopal visitations, parish records, and occasional pamphlets. Politics of recognition, which is much more common in a modern context, in this case means the way the political authorities dealt with this multi-confessional region and their recognition or non-recognition of the various groups as distinct.