[a] His title to the metropolitan see was acknowledged both by the Holy See and by the Ecumenical Patriarchate of Constantinople due to their joint acceptance of the Council of Florence which united the Latin and the Eastern Orthodox Churches for a short period of time.
His canonical territory was the western part of the traditional Kievan Rus' lands — the states of the Grand Duchy of Lithuania and the Kingdom of Poland.
In 1448, Russian bishops in Moscow, who had rejected the Union with Rome, elected Jonah as Metropolitan of Kiev and all Rus'[2] without the consent of Constantinople.
[5][6] At least two more diocesan bishops of Great Novgorod and Tver chose to abstain in selection either side.
The metropolis within the Polish kingdom and the Grand Duchy of Lithuania remained therefore in communion with the Holy See, as well as during the rule of the following metropolitan Міsail (1476–1480).