Petro Parfenii was an Orthodox Bishop who united the Ruthenian Church with Rome. In 1646, 63 Ruthenian priests (under Parfenii’s leadership) solicited a union with the Catholic Church. However, they required the preservation of the Byzantine Rite, Canon law and the ecclesiastical authority.
The Catholic Church recognized Parfenii as bishop in 1655 (due to Parfenii’s ordination by an Orthodox metropolitan in 1651). In 1664, Parfenii established himself in Mukacheve. Parfenii died in 1665.