c. 49
Council of Jerusalem
The apostles and elders at Jerusalem decide that Gentile converts need not be circumcised or keep the whole law; the decision that makes a Gentile church possible.
Christianity
The Eastern Orthodox stream of the Christianity timeline.
Streams: All of Christianity Catholic Eastern Orthodox Oriental Orthodox Anglican Lutheran Reformed and Presbyterian Anabaptist Baptist Methodist and Wesleyan Restorationist Pentecostal and Charismatic Independent and Non-denominational
Apostolic
Patristic
325
First Council of Nicaea
Constantine convenes the first ecumenical council at Nicaea, which condemns Arius and confesses the Son as homoousios; of the same being as the Father; in the original Nicene Creed.
330
Founding of Constantinople
Constantine dedicates his new capital on the Bosporus; the New Rome becomes the seat of the eastern church and empire for a thousand years.
367
Athanasius' 39th Festal Letter
Athanasius of Alexandria's Easter letter lists the twenty-seven books of the New Testament; the earliest surviving list that matches the church's canon exactly.
381
First Council of Constantinople
The second ecumenical council completes the Nicene confession, expanding the article on the Holy Spirit; its creed is the Nicene-Constantinopolitan Creed the church still recites.
431
Council of Ephesus
The third ecumenical council condemns Nestorius and confesses Mary as Theotokos, God-bearer; the Church of the East separates in the aftermath; the first lasting schism.
451
Council of Chalcedon
The fourth ecumenical council confesses Christ in two natures, without confusion or separation; the churches that refuse the definition become the Oriental Orthodox communion.
553
Second Council of Constantinople
The fifth ecumenical council condemns the Three Chapters in Justinian's bid to reconcile the Chalcedonian and non-Chalcedonian churches; the reconciliation fails.
680–681
Third Council of Constantinople
The sixth ecumenical council condemns Monothelitism and confesses two wills in Christ, vindicating Maximus the Confessor a generation after his death.
787
Second Council of Nicaea
The seventh ecumenical council restores the icons and defines the distinction the church still uses: veneration (proskynesis) for images, true worship (latreia) for God alone.
Medieval
1054
Great Schism
Legates of Leo IX lay a bull of excommunication on the altar of Hagia Sophia and Patriarch Cerularius answers in kind; the mutual anathemas formalize the rupture between Rome and Constantinople.
1204
Fourth Crusade Sacks Constantinople
Diverted crusaders storm and sack Constantinople, enthroning a Latin emperor and patriarch; the outrage hardens the schism of 1054 into permanence.
1453
Fall of Constantinople
Mehmed II takes Constantinople after a fifty-three-day siege; the Byzantine Empire ends, and the Orthodox world passes under Ottoman rule.
Contemporary
1948
World Council of Churches Founded
The World Council of Churches constitutes itself at Amsterdam under the theme 'Man's Disorder and God's Design', joining the historic churches in one fellowship; Rome observing from outside.