The key point of this paper is the process of State building in Greece during the XXth Century. This is approached by focusing on the interplay between the State and denominational communities, from 1913 to 1939. Located on the borders of Greece and Albania, Epirus constitutes, from that standpoint, a relevant case study. During the interwar period, this poor and mostly mountainous area is characterized by the coexistence of several denominational communities and the porosity of political borders. In this context, religious factors got intertwined with major sociopolitical issues such as the settlement of a great number of refugees; state building on new ter r itories; land property; education and national integration; public order and defence. The intricacies of this situation contributed to keep the higher clergy within the political field. The case of the Orthodox bishopric of Ioannina, in the Greek part of Epirus, clearly illustrates this tendancy. Although the close connections between the Orthodox Church and nationalism made easier the social control of local population, the bishops, however – who held not only religious but also political power in the preexisting Ottoman system – kept ambiguous and sometimes strained relationships with State authority and its representatives.