Christianity in Russia is the most widely professed religion in the country, with nearly 71% of the population identifying as Orthodox Christian according to World Atlas. The largest tradition is the Russian Orthodox Church. According to official sources, there are 68 eparchies of the Russian Orthodox Church. There are from 500,000 to one million Old Believers, who represents an older form of Russian Orthodox Christianity, and who separated from the Orthodox Church in the 17th century as a protest against Patriarch Nikon's church reforms.