For over 600 years the Russian Orthodox Church followed the liturgical ritual as it was handed down from their Greek baptizers. In the mid-17th century, however, Patriarch Nikon was encouraged by contemporary theological scholarship, both Greek and Russian, to institute certain changes and service book revisions. Strong opinions on both sides of the issue led to the Russian Council of 16661667 in which the opposition to the reforms were anathematized and even the Old Rite itself was condemned. Those who continued to adhere to the old practices became known as "Old Ritualists" (Staro-obriadtsi) and/or "Old Believers" (Staro-veri).
Efforts towards reconciliation made over the last 300 years were never very successful, in spite of the fact that the difference between the two groups involved no issues of dogma. Finally, in 1974, the Russian Orthodox Church Outside of Russia issued an ukase recognizing the Old Rite as fully Orthodox and salvific, and allowing the ordination of priests according to the Old Rite to serve the liturgical services according to the Old Rite. (It should be understood that this is not a different rite, but simply a variation of what is observed by the rest of the Russian Orthodox Church.)[OA/_private/oabot.htm]