The analyses of transnational actors role in international dynamics, as well as foreign policy analyses and the impact of religious elements over international relations is a very important field of studies in today s International Relations disciplines. In this dissertation we propose a new look over the construction of the well based unwritten alliance between Brazil and United States, investigating the possible participation of Presbyterian North-American missionaries in the building of the solid friendship between these two countries. The research is based on case specific analyses, with use of primary and secondary sources of study, oriented by different theoretical resources of International Relations directed to the analyses of transnational actors, foreign policy analyses e norms analyses.