In terms of religious affiliation, ethnic Ukrainians are exclusively Christian, professing an ancient and traditional form of Christianity: the Eastern Greek (or Byzantine) rite. Many Ukranians belong to the Ukrainian Orthodox Church; others, primarily in western Ukraine, to the Ukrainian Greek Catholic Church. Ukrainians were baptized en masse c. 988 by the Grand Duke of Kyiv, Volodymyr, thereby adopting Greek Rite Christianity from Constantinople. The first bishops and metropolitans (seated in Kyiv and Halych) in Ukraine were Greeks, later natives. Prior to 1700, the Ukrainian Orthodox Church was subject to the Ecumenical Patriarch in Constantinople. Around three hundred years ago, it was transferred to the Moscow Patriarch. After independence in 1991, the Ukrainian Orthodox Church separated from the Moscow Patriarch and Filaret (born Denysenko), who had been metropolitan of Kyiv for 40 years, was elected the independent Ukrainian Patriarch.
The largest group of Ukrainians belong to the Ukrainian Orthodox Church. The Ukrainian Greek-Catholic Church (numbering over 5 million believers) is headed by Sviatoslav Shevchuk, and is in full communion with the Holy See. Evangelical Protestantism is also known in Ukraine - some Ukrainians have become either Pentecostals or Baptists. Islam is foreign to Ukraine, some Muslims can be found among non-Ukrainian groups such as Crimean Tatars on the Crimean peninsula (currently under Russian rule) and Asian immigrants.