ENThere is a lot of information and discussion on the issues related to the foundation of the Dominican Monastery and Church of St Mary in Seinai. Therefore, the article deals with the modern religious architecture of the territory of the Polish-Lithuanian Commonwealth, the Grand Duchy of Lithuania and Germany. In this context, a comparative analysis of the buildings from the 17th and 18lh centuries was made. Not only, were the foundations of Dominicans taken into account, but also those which belonged to the other religious orders, including the Jesuits and Bernardines who were active in the region. The influence of strong local traditions and local communities was also taken into consideration. The Dominican Monastery and Church of St Mary in Seinai is compared with such architectural masterpieces as the Cathedral of St. Mary and St. John the Evangelist in Kwidzyn, together with the adjacent castle from the west, the foundation of the Royal Marshall Łukasz Opaliński and his wife Anna of Pileckich for Bernardine in Leżajsk, as well as the Benedictine Abbey in Ottobeuren in Swabia. The attention was also paid to the architectural projects of Joseph Furttenbach (Architecture! recreationis) and Sebastian Serlio (Book III, the project of Poggio Reale villa).