ENThe article focuses on the rivalry between Orthodox and Catholic communities for the domination in the city. It is believed that the key events which helped escalate inter-religious tension in Vilnius were the attachment of the Ukrainian Greek Catholic Church to the Orthodox Church in 1839 and the relocation of the centre of the Consistory of the Lithuanian Orthodox Church from Zhirovichi (Grodno governorate) to Vilnius (1845). The central figure in the deliberate or non-deliberate escalation of the conflict between the Catholic and the Orthodox Church was Joseph Semashko, metropolitan bishop of the Orthodox Church. An odd policy of "intervention" aimed at the entrenchment of the leading position of the Orthodox Church in the Catholic north-western governorates and Vilnius was pursued on his initiative. The 1840s–1850s witnessed the initial phase of penetration, first of all characterized by the material entrenchment of the "new" representatives of the Orthodox Church (i.e. first and foremost those converted from the Ukrainian Greek Catholic Church). Transfer of buildings confiscated from Catholics by the Tsar’s government to the Orthodox Church, their conversion into Orthodox churches, consecration, establishment of relationships with the local authorities, first attempts to restrain the public religious life of Catholics, etc. which took place after the November Uprising (1831) were leading to a direct confrontation with the Catholic Church and violations of the traditionally settled life of the city’s religious communities. Although no overt conflicts between Vilnius religious communities were detected in the relevant period, the escalating religious tension was obvious in the described events.Despite the fact that the bigger share of the intended religious policy of "intervention" failed to achieve its goals, it can be stated that it laid grounds for the Orthodoxization and Russification processes initiated after 1863. [From the publication]