It is known that by the 9th century the Slavic population of western Ukraine (likely the White Croats) had accepted Christianity while under the rule of Great Moravia. However, it was the East Slavs who came to dominate most of the territory of present-day Ukraine, beginning with the rule of the Rus whose pantheon of gods had held a considerable following for over 600 years.

After the 860 assault on Constantinople by Rus’ forces under the command of Askold and Dir, the two princes were baptized in that holy city. Returning to Kiev, the two actively championed Christianity for a period of 20 years. They were murdered by the pagan Prince Oleg in the inter-princely rivalry for the Kiev throne. Patriarch Photios purportedly provided a bishop and priests from Constantinople to help in the Christianization of the Slavs. By 900, a church was already established in Kiev, St. Elijah’s, modeled on a church of the same name in Constantinople. This gradual acceptance of Christianity is most notable in the Rus-Byzantine Treaty of 945, which was signed by both “baptized and unbaptized Rus”, according to the text included in the Primary Chronicle.

St. Sophia’s Ukrainian Greek-Catholic Church in Kiev, Ukraine

Christianity’s acceptance among the Rus nobility gained a vital proponent when Princess Olga, the ruler of Kiev, became baptized, taking the Christian name Helen. Her baptism in 955 (or 957) in either Kiev or Constantinople (accounts differ) was a turning point in religious life of Rus but it was left to her grandson, Vladimir the Great to make Kievan Rus a Christian state. Princess Olga of Kiev, shortly after her baptism, appealed to the Holy Roman Emperor Otto the Great to send missionaries to Rus. Saint Adalbert, a Roman Catholic missionary bishop from Germany, was sent, but his missionary activities and the priests who were with him, were stopped. Most of the group of Latin missionaries were slain by pagan forces sent by Prince Svyatoslav, who had taken the crown from his mother.

Christianity became dominant in the territory with the mass Baptism of Kiev in the Dnieper River in 988, ordered by Vladimir. That year is considered as the year of the establishment of the Kiev Metropolis which was a part of the Patriarchate of Constantinople. The exact date of establishment is not clearly known as the Kiev Eparchy is mentioned as early 891. The first cathedral, Church of the Tithes (Assumption of the Virgin Mary), was built in 996.

After the Great Schism in 1054 the Church in Ukraine remained in union with Constantinople. It was not until 1596, with the Union of Brest, that the western portion of Ukraine entered into union with the Roman Catholic Church. It was then that our Ukrainian Greek-Catholic Church came into existence. More about the Union of Brest in the coming issues.