Constantinople
The city on the Bosphorus that Constantine rebuilt from Greek Byzantium and dedicated in 330 as New Rome. It was the capital of the eastern Roman empire and the seat of the bishop who ranked next after the bishop of Rome.
Constantinople stands on a promontory at the southern end of the Bosphorus, where Europe faces Asia. Constantine renamed the older city of Byzantium after himself (Origo Constantini 6.30), enlarged and walled it, and decreed that it should be called New Rome (Socrates, Church History 1.16); see Constantine Dedicates Constantinople. Councils met there in 381 and later, and the first of them gave its bishop a rank of honour second only to that of Rome (Council of Constantinople (381) canon 3). It is the modern Istanbul.
What happened here
- 11 May AD 330, firm dateConstantine Dedicates Constantinople
Constantine rebuilds Byzantium on the Bosphorus as a new imperial city, names it after himself and dedicates it on 11 May 330. He means it to equal Rome and calls it New Rome, and in 381 its bishop is ranked next after the bishop of Rome.
- AD 359 to AD 360, firm dateThe Councils of Rimini and Seleucia
The emperor Constantius II summons the western bishops to Rimini and the eastern to Seleucia. Under imperial pressure the delegates of both accept a creed that calls the Son like the Father and forbids the Nicene language of substance.
- AD 361 to AD 363, firm dateJulian Tries to Restore the Old Religion
Julian, a nephew of Constantine, renounces the Christianity in which he was raised, reopens the temples and bars Christians from teaching the classics. He dies on campaign in Persia after less than two years as sole ruler.
- about AD 370 to AD 381, estimated dateThe Cappadocians and the Doctrine of the Trinity
Basil of Caesarea, his friend Gregory of Nazianzus and his brother Gregory of Nyssa speak of one divine essence in three persons and defend the deity of the Holy Spirit. The creed of 381 uses kindred language. Basil and his sister Macrina foster monastic life.
- 27 February AD 380, firm dateThe Edict of Thessalonica
By an edict issued at Thessalonica, the emperor Theodosius orders all his peoples to hold the faith of the bishops of Rome and Alexandria in the one deity of Father, Son and Holy Spirit. Christians who believe otherwise are declared heretics.
- May AD 381, firm dateThe First Council of Constantinople
About 150 eastern bishops, summoned by Theodosius, confirm the faith of Nicaea, condemn those who deny the full deity of the Son or of the Spirit, and rank the bishop of Constantinople next after Rome. The creed now recited in most churches bears this council’s name.
- AD 398 to AD 407, firm dateJohn Chrysostom, Preacher and Exile
John, a presbyter of Antioch known for his preaching, is made bishop of Constantinople in 398. His reforms and his plain speaking make enemies among the clergy and at court. A synod deposes him, the emperor banishes him twice, and he dies in exile in 407.
- AD 482 to AD 519, firm dateThe Henotikon and the Acacian Schism
The emperor Zeno tries to reunite the supporters and opponents of Chalcedon with a statement of faith that neither adopts nor expressly condemns the council. Rome answers by declaring Acacius of Constantinople deposed, and the two sees stay out of communion for thirty-five years.
- 27 December AD 537, firm dateJustinian Builds Hagia Sophia
After rioters burn the cathedral of Constantinople in 532, the emperor Justinian rebuilds it as a vast domed church, dedicated on 27 December 537. In the same years he sets out in law his view of priesthood and empire as two gifts of God.
- about AD 542 to AD 578, estimated dateJacob Baradaeus and the Syriac Orthodox Church
When the opponents of Chalcedon are short of bishops, the empress Theodora has the monk Jacob consecrated. John of Ephesus, his admirer, tells how he travelled the East for over thirty years, hunted by the emperor’s agents, ordaining clergy and bishops for a separate church.
- AD 553, firm dateThe Second Council of Constantinople
A council called by the emperor Justinian condemns the “Three Chapters”, writings of three theologians linked with Nestorius, and restates the faith of Chalcedon in fourteen anathemas. Pope Vigilius first refuses and then accepts; parts of the West resist for decades.
- AD 680 to AD 681, firm dateThe Third Council of Constantinople
A council called by the emperor Constantine IV defines that Christ has two wills and two operations, divine and human, never opposed. It condemns the teaching of one will and those who had upheld it, among them four patriarchs of Constantinople and Pope Honorius.
- AD 726–730, estimated dateThe Iconoclast Controversy Begins
The emperor Leo III moves against religious images, and the patriarch Germanus resigns rather than consent. John of Damascus writes in their defence from outside the empire. In 754 a council under Leo’s son condemns images as contrary to the doctrine of Christ.
- 11 March AD 843, estimated dateThe Triumph of Orthodoxy
After the death of the iconoclast emperor Theophilus, his widow Theodora and the new patriarch Methodios restore the veneration of icons at Constantinople. The day is kept each year on the first Sunday of Lent.
- AD 863 to AD 867, estimated dateThe Photian Schism
Pope Nicholas I refuses to recognize Photius as patriarch of Constantinople and declares him deposed; Photius denounces Latin teaching in Bulgaria, the filioque above all, and his council condemns the pope. The breach is healed, but its arguments return.
- AD 864–866, estimated dateThe Baptism of Boris and the Conversion of Bulgaria
Boris, ruler of the Bulgars, accepts baptism from Constantinople and takes the name Michael. He puts down a revolt of his nobles, then asks the pope for bishops, and his country becomes a prize in the quarrel between Rome and Constantinople.
- November AD 879 – March 880, firm dateThe Council of Constantinople Restores Photius
A council at Constantinople, with legates of Pope John VIII, recognizes Photius as patriarch, rejects the council that had condemned him ten years earlier and forbids any change to the creed. Orthodox documents count it among the councils of universal authority.
- 16 July 1054, firm dateThe Schism of 1054
Legates of the Roman see excommunicate the patriarch of Constantinople in Hagia Sophia, and his synod anathematizes them in return. The sentences name persons, not churches, but later ages take the day as the breach between East and West.
- 1095 to 1099, firm dateThe First Crusade
In 1095 Pope Urban II calls the knights of the West to go east in arms for the remission of their sins. Four years later the armies storm Jerusalem and massacre its defenders and inhabitants, as their own writers report.
- April 1204, firm dateThe Fourth Crusade Sacks Constantinople
A crusading army, carried by a Venetian fleet it cannot pay for, turns on Constantinople, storms it and plunders its churches. Pope Innocent III condemns the sack, but a Latin emperor is installed and the conquest stands.
- 1341 to 1351, firm dateGregory Palamas and the Hesychast Councils
Councils at Constantinople in 1341 and 1351 uphold the monk Gregory Palamas against Barlaam. God’s essence is beyond reach, they teach, but his uncreated energies, seen as the light of Tabor, are shared by the saints. The Orthodox Church holds this teaching as its own.
- 29 May 1453, firm dateThe Fall of Constantinople
After a siege of some eight weeks the Ottoman sultan Mehmed II takes Constantinople on 29 May 1453. The last emperor, Constantine XI, dies in the fighting, Hagia Sophia becomes a mosque, and the sultan makes the anti-unionist monk Gennadius patriarch.
- 26 January 1589, firm dateMoscow Becomes a Patriarchate
In January 1589 Jeremias II of Constantinople, visiting Russia, installs Metropolitan Job as the first patriarch of Moscow. A council at Constantinople confirms it in 1590 and ranks Moscow fifth. The tsar’s charter calls the Russian realm the Third Rome.
- 1915 to 1916, firm dateThe Destruction of the Armenian and Assyrian Christians
From April 1915 the Ottoman government deports Armenians from across the empire toward the Syrian desert, and the American ambassador reports massacre, starvation and the destruction of a people. Assyrian Christians of Urmia and Hakkari are attacked in the same months.
- 7 December 1965, firm dateRome and Constantinople Lift the Anathemas of 1054
On 7 December 1965 Pope Paul VI and Patriarch Athenagoras I declare together that they regret the excommunications exchanged in 1054 and remove them from the memory of the church. The act does not restore communion between the two churches.
- 6 January 2019, firm dateConstantinople Grants Autocephaly to the Orthodox Church of Ukraine
The Ecumenical Patriarch Bartholomew hands Metropolitan Epiphanius a tomos declaring the Orthodox Church in Ukraine autocephalous. The Moscow Patriarchate, which counts Ukraine as its own canonical territory, has already broken communion with Constantinople over the decision.
- 28 November 2025, firm dateThe Churches Mark 1,700 Years since Nicaea
Pope Leo XIV, the Ecumenical Patriarch Bartholomew and leaders of other churches pray together at İznik, the ancient Nicaea, and profess the creed. The next day pope and patriarch sign a declaration naming the faith of Nicaea as what binds Christians together.