Patriarch Nikon, the most energetic, creative, influential, and obstinate of Russia's early religious leaders, dominates this book. As Patriarch of the Russian Orthodox Church, Nikon's most important initiative was to bring Russian religious rituals into line with Greek Orthodox tradition, from which Russia's practices had diverted. Kiev's Monastery of the Caves served as a medium for his transmission of Greek notions. Nikon and Tsar Alexis I (r. 1645-1676) envisioned Russia's transformed into a new Holy Land. Eventually, Nikon became a challenger for Imperial authority. While his reforms endure, failed policies and poor political judgment were decisive in his fall and in the Patriarchate's reduction in status. Ultimately, the reforms of Peter the Great (r. 1682-1725) led to its replacement by a new, government-controlled body, the Holy Synod, which nevertheless carried out a continuity of Nikon's policies. This exceptional volume contextualizes Nikon's Patriarchate as part of the broader continuities in Russian History and serves as a bridge to the present, where Russia is forging new relationships between Church and power.