The history of the Russian Orthodox Church begins with the Christianization of Kievan Rus' in 988 during the reign of Vladimir the Great. In the following centuries, Kiev and later other cities, including Novgorod, Pskov, Rostov, Suzdal and Vladimir, became important regional centers of Christian spirituality and culture. Following the Mongol invasions of the 13th century, the seat of the metropolitan was moved to Vladimir in 1299, and then to Moscow in 1325, which would become the spiritual center of Russian Orthodoxy.
The metropolitans of the Russian Church supported the rise of the Moscow principality and his presence increased the Muscovite prince's authority and ambition to unify the lands. In turn, the metropolitans were able to increase the stability of the Church and to inspire unity among the divided Russian principalities. By the mid-15th century, Moscow was both the political and religious center of the country. The Russian Church declared autocephaly in 1448, shortly before the fall of Constantinople, owing to its protest over the Council of Florence. At the behest of the grand prince of Moscow, a council of Russian bishops elected a local bishop without the approval of Constantinople.