Orientales Omnes Ecclesias §19

¹⁹ However it came about by the inscrutable will of God that towards the end of the century this community was harassed by many persecutions and vexations, and after the partition of Poland these became ever harder and more bitter in the areas which were annexed to the Russian Empire. After the death of Alexander I the rash policy was deliberately adopted of entirely breaking the union of the Ruthenians with the Roman Church. Already most of their eparchies had been almost cut off from any intercourse with the Apostolic See. Soon bishops were chosen who were imbued and inspired with zeal for schism, and so would become the lackeys and applauders of the civil power. In the seminary of Vilna, founded by the tsar Alexander I, teaching hostile to the Roman pontiffs was imparted to the clergy of both rites. The Basilian Order, whose members had always been a great support to the Catholic Church of the Eastern rite, was deprived of its own government and administration, and its monks and monasteries were entirely subjected to the consistories of the eparchies. Then the priests of the Latin rite were prohibited under grave penalties from administering the sacraments or other religious helps to the Ruthenians. Finally, alas, in 1839 the union of the Ruthenian Church with the dissident Russian Church was solemnly proclaimed.