Autocephaly of the Russian Church
Jonah's elevation in 1448 followed the deposition of Metropolitan Isidore, who had embraced union with Rome at the Council of Florence. Because Jonah was consecrated in Moscow by Russian hierarchs rather than confirmed beforehand by the Ecumenical Patriarch of Constantinople — as had been the established practice — his appointment is treated as the beginning of the de facto autocephaly of the Russian Orthodox Church, the first time Russian bishops consecrated their own metropolitan.