The Council of Florence: Did the Orthodox Church Accept Union With Rome?
In 1439, something extraordinary happened.
Eastern and Western bishops gathered at the Council of Florence and signed a decree announcing the restoration of communion between the Greek East and the Roman West.
The decree, Laetentur Caeli—“Let the heavens rejoice”—addressed several of the very issues that still divide Catholics and Orthodox:
- the filioque;
- purgatory;
- the use of leavened or unleavened bread;
- papal primacy.
Most of the Eastern delegation signed.
One of the most important bishops refused: Mark of Ephesus.
The union then collapsed.
Catholic polemics sometimes say:
“The Orthodox Church accepted reunion at Florence and later rejected an ecumenical council.”
Orthodox polemics sometimes answer:
“Florence was simply a fake council where the Greeks were forced to sign.”
Both statements oversimplify the history.
Why Was the Council Called?
By the fifteenth century, the Byzantine Empire was in desperate danger.
The Ottoman Turks had reduced Byzantine territory dramatically. Constantinople itself faced an existential threat.
Emperor John VIII Palaiologos hoped that reunion with Rome might secure military assistance from the West.
This political pressure is impossible to remove from the story.
But it does not follow that every Greek theological discussion was insincere.
The Eastern delegates included serious bishops and theologians. They debated Latin representatives at length. The union was political and theological.
From Ferrara to Florence
The council initially met at Ferrara in 1438 and later moved to Florence.
The Greek delegation included the emperor, Patriarch Joseph II of Constantinople, bishops, monks, and scholars.
The discussions were difficult.
The filioque dominated much of the debate. The Greeks challenged both the theology of the addition and the Western Church’s authority to insert it into the Creed.
Purgatory and papal authority were also major obstacles.
Over time, the pressure for agreement intensified.
The Death of Patriarch Joseph II
Patriarch Joseph II died shortly before the final union decree.
A statement supportive of union was attributed to him, but he did not personally participate in the final signing ceremony.
His death removed an important figure from the Greek delegation at a critical moment.
That detail matters because later presentations sometimes imply a cleaner institutional assent than actually existed.
What Did Florence Teach About the Filioque?
The decree of union taught that the Holy Spirit is eternally from the Father and the Son and has his essence and subsistent being from both.
It also said the Spirit proceeds from the Father and the Son “as from one principle and by one spiration.”
At the same time, the council attempted to reconcile this with the Greek formula “through the Son.”
For Catholics, Florence showed that the Greek and Latin traditions could be harmonized.
For many Orthodox, the language of Father and Son as “one principle” still compromised the Father’s unique monarchy.
The verbal bridge did not eliminate the deeper theological concern.
What Did Florence Say About Purgatory?
The decree affirmed postmortem purification for those who die in charity but still require cleansing.
It also affirmed that the prayers, Masses, almsgiving, and other acts of the living can benefit the departed.
The Greeks already practiced prayer for the dead.
The controversy concerned the explanatory Latin framework and especially debates over purgatorial fire and satisfaction.
Florence did not force every popular Western image of purgatory into the final decree, but it preserved the substantive Catholic doctrine of postmortem purification.
What Did Florence Say About the Pope?
The decree affirmed that the Roman pontiff is the successor of Peter, the true Vicar of Christ, head of the whole Church, father and teacher of all Christians, and that to him was given full power to feed, rule, and govern the universal Church.
That language is unmistakably strong.
Catholics regard it as ecumenical confirmation of papal primacy.
Orthodox critics note that the final clause says this authority exists “as is contained also in the acts of the ecumenical councils and in the sacred canons,” leaving unresolved how the older canonical tradition should delimit such power.
The Orthodox Church never received Florence’s papal formulation as its own ecclesiology.
Why Did Most Greeks Sign?
There was no single reason.
Some became persuaded, at least to some degree, by Latin theological arguments.
Some desired church unity.
Some feared the collapse of Byzantium.
Some experienced political and practical pressure from the emperor and the circumstances of the council.
The Greeks had also been away from home for a prolonged period and were financially dependent on Western hosts.
It would be simplistic to describe every signature as free of pressure.
It would also be simplistic to say no signer believed the agreement.
Historical actors can have mixed motives.
Mark of Ephesus
Mark Eugenikos, metropolitan of Ephesus, became the great symbol of Orthodox resistance.
He refused to sign the decree.
His opposition centered especially on the filioque, purgatory, and Roman claims.
According to later tradition, when Pope Eugene IV learned that Mark had not signed, he recognized how serious a problem this was for the union.
Mark returned East and became the leading theological voice against Florence.
Orthodox Christians later venerated him as St. Mark of Ephesus.
He should not be romanticized as if he single-handedly represented every Greek thought at the council. But his refusal became historically decisive because the union lacked broad reception once the delegation returned home.
Reception in Constantinople
This is where Florence’s story changes.
Signing a conciliar decree was not the end of the matter.
Many clergy, monks, and laity in the East opposed the union. Some signers later repudiated or distanced themselves from their signatures.
The union could not be implemented as a stable ecclesial reality.
A formal union service was eventually celebrated in Hagia Sophia in December 1452, only months before Constantinople fell to the Ottomans in May 1453.
But the reunion never became the lived faith of the Orthodox churches as a whole.
Did the Fall of Constantinople End the Union?
The Ottoman conquest certainly transformed the political landscape, but the union was already deeply unpopular.
It would therefore be misleading to say Florence would have succeeded if Constantinople had simply survived.
The problem was ecclesial reception.
The Eastern Christian body did not recognize the council as a legitimate ecumenical settlement of the disputed doctrines.
What Does “Reception” Mean?
Florence highlights a fundamental difference in Catholic and Orthodox concepts of council authority.
In current Catholic doctrine and canon law, an ecumenical council is an exercise of the episcopal college together with—and never apart from—its head, the Roman pontiff. The pope alone convokes an ecumenical council under current law, and its decrees require papal approval, confirmation, and promulgation to have binding force.
Orthodoxy places greater emphasis on the Church’s reception of a council as genuinely expressing the apostolic faith.
This does not mean Orthodox councils are decided by opinion poll.
Nor does it mean every later dissenter can invalidate a council.
It means that a council’s claim to ecumenicity is ultimately manifested by its enduring reception in the whole Church under the Holy Spirit.
Florence was not so received in Orthodoxy.
Was Florence a Robber Council?
That label can also obscure more than it clarifies.
Florence was a major, sophisticated theological council involving senior representatives of East and West.
It produced serious texts and deserves careful study.
From a Roman Catholic standpoint, it is an ecumenical council.
From an Eastern Orthodox standpoint, it is a failed reunion council whose theological settlement was not received by the Church.
Saying this is more precise than pretending nothing happened—or pretending Orthodoxy permanently accepted reunion in 1439.
Final Verdict
Yes, most of the Greek delegation at Florence signed a formal reunion decree with Rome. No, the Orthodox Church as a whole did not ultimately receive that union as binding or orthodox.
Both facts must be kept together.
Florence cannot honestly be dismissed as though no Eastern bishops agreed.
But neither can a set of signatures under extraordinary political and ecclesiastical circumstances be equated automatically with lasting reception by the Orthodox Church.
The council’s failure reveals the deeper issue beneath every doctrinal dispute:
What makes a council truly ecumenical and binding on the whole Church?
Catholics and Orthodox answer that question differently.
For Rome, Florence stands as an ecumenical council and a major witness to Catholic teaching.
For Orthodoxy, its rejection demonstrates that neither imperial pressure nor episcopal signatures alone can manufacture catholic reception.
That is why Florence remains one of the most important episodes for understanding the Catholic–Orthodox divide.
Key Sources
Primary and official sources
- Council of Florence, Laetentur Caeli (1439).
- Proceedings and records of the Council of Ferrara–Florence.
- Writings of Mark of Ephesus.
- Byzantine accounts surrounding the council and its reception.
- Catholic conciliar collections concerning Florence.
Modern scholarship
- Joseph Gill, The Council of Florence.
- Deno John Geanakoplos, studies of Byzantium and Renaissance Italy.
- John Meyendorff, Byzantine Theology.
- A. Edward Siecienski, The Filioque and The Papacy and the Orthodox.