Moscow ? In his nearly two decades at the head of the world’s largest Orthodox church, Patriarch Alexy II oversaw a religious revival in Russia and healed a major church rift, but his death leaves a long-running dispute with the Vatican unresolved.

Alexy’s death Friday at age 79 deprives the Russian Orthodox Church of its dominant figure, whose stern, bearded mien gave him an almost medieval aura of inflexible righteousness. He often complained that Roman Catholics were poaching adherents among a people who traditionally would have been Orthodox if atheistic Soviet rule had not impeded them.

Yet he and the church held many discussions with the Vatican, aiming to reach an agreement that would allow the church to accept a papal visit to Russia.

The Moscow Patriarchate did not give a cause of death.