During the reign of St. Vladimir the Great, the people of Kievan Rus’ (map) were baptized in 988. In Kiev, an estimated 350,000 Orthodox faithful took part in a procession led by bishops of the the Ukrainian Orthodox Church (Moscow Patriarchate).

Major Archbishop Sviatoslav Shevchuk, the head of the Ukrainian Greek Catholic Church, issued a statement in which he also recalled the 425th anniversary of the Union of Brest, in which several Orthodox bishops entered into full communion with the Catholic Church.