Council of Ferrara-Florence,ecumenical council of the Roman Catholic church (1438–45) in which the Latin and Greek churches tried to reach agreement on their doctrinal differences and end the schism between them. The council ended in an agreed decree of reunion, but the reunion was short-lived. The Council of Ferrara-Florence was not a new council but was the continuation of theCouncil of Basel, which PopeEugenius IV transferred from Basel and which opened inFerrara on Jan. 8, 1438. The Greek delegation, numbering about 700, included the patriarch of Constantinople Joseph II, 20 metropolitans, and theByzantine emperorJohn VIII Palaeologus.

Discussions were held onpurgatory and on the phraseFilioque (“and from the Son”) of theNicene Creed, which sets forth the doctrine that theHoly Spirit proceeds from both the Father and the Son. The Greeks held that the Spirit proceeds from the Father only and had refused to accept theFilioque.

On Jan. 10, 1439, the council was moved from Ferrara toFlorence when a plague hit Ferrara. After much discussion, the Greeks agreed to accept theFilioque and also the Latin statements on purgatory, theEucharist, and papal primacy. The decree of union between the two groups (Laetentur Caeli) was signed on July 6, 1439. After their return to Constantinople, many of the Greeksrepudiated the reunion. Meanwhile, the Latins completed union agreements with certain other Eastern churches. Noextant document records the closing of the council, which moved toRome in September 1443.

Doctrinally, the council is of interest because of the exposition of the Catholic doctrines of purgatory and of the primacy andplenary powers of the pope set out inLaetentur Caeli. The decree for union with the Armenians contains a long exposition of sacramental theology.