The Metropolis of Moscow and all Rus () was a metropolis that was unilaterally erected by hierarchs of the Eastern Orthodox Church in the territory of the Principality of Moscow in 1448. The first metropolitan was Jonah of Moscow; he was appointed without the approval of the Ecumenical Patriarch of Constantinople. The metropolis split from the Metropolis of Kiev and all Rus' because the previous metropolitan — Isidore of Kiev — had accepted the Union of Florence. Seventeen prelates succeeded Jonah until Moscow's canonical status was regularised in 1589 with the recognition of Job by the Ecumenical Patriarch. Job was also raised to the status of patriarch and was the first Patriarch of Moscow.
The Moscow Patriarchate was a Caesaropapist entity that was under the control of the Russian state. The episcopal seat was the Dormition Cathedral in Moscow.
Background
thumb|right|[[Jonah of Moscow, the first metropolitan of Moscow and all Rus' since 1448]]
An Ecumenical council of the Church — the Council of Florence — took place from 1431 to 1449. Although he resisted at first, the Grand Prince of Moscow — Vasily II of Moscow — eventually permitted the Metropolitan of Kiev and all Rus' — Isidore of Kiev — to attend the council on condition that Isidore should return with "the rights of Divine law and the constitution of the holy Church" uninjured. The council healed the Great Schism by uniting the Roman Catholic and Eastern Orthodox churches. The union was proclaimed on 6 July 1439 in the document Laetentur Caeli which was composed by Pope Eugene IV and signed by the Holy Roman Emperor Sigismund and all but one of the bishops present. Some Greek bishops, perhaps feeling political pressure from the Byzantine Emperor, reluctantly accepted the decrees of the council. Other Eastern bishops, such as Isidore, did so with sincere conviction. Sylvester Syropoulos and other Greek writers charge Isidore with perjury because he accepted the union, despite his promise to Vasili II.
Following the signing of the bull, Isidore returned to the Principality of Moscow. In the Kremlin's Dormition Cathedral, Isidore read the decree of unification aloud. He also passed a message to Vasili II from the Holy See, containing a request to assist the metropolitan in spreading the Union in Rus'. Three days later, Isidore was arrested by the Grand Prince and imprisoned in the Chudov Monastery. He arranged for certain Rus' clergy to denounce the metropolitan for refusing to renounce the union with Rome. As a result, the Great Prince of Moscow voided the union in his lands and imprisoned Isidore for some time.
Establishment
After the metropolitan throne lay vacant for seven years, the secular authorities replaced him with the Bishop of Ryazan and Murom — Jonah of Moscow. Like his immediate predecessors, he permanently resided in Moscow, and was the last Moscow-based primate of the metropolis to keep the traditional title with reference to the metropolitan city of Kiev. He was also the first metropolitan in Moscow to be appointed without the approval of the Ecumenical Patriarch of Constantinople as had been the norm. Afterwards, the Muscovite principality and metropolis began to promote Moscow as the "Third Rome" and as the sole, legitimate successor to Constantinople.
Notwithstanding these events, the Ecumenical Patriarch continued to appoint metropolitans for the united Catholic and Eastern Orthodox ("Uniate") dioceses in those Ruthenian lands that were not controlled by the Tsardom of Moscow. In the Polish and Lithuanian lands, the next uniate hierarch