Chronology of the Great Schism

c. 399-415 Augustine, De Trinitate

589 Council in Toledo adds "filioque" to Nicene Creed (locally).

725 Iconoclastic controversy breaks out in East

751 Peppin (father of Charlemagne) asks Pope Zacharias to rule on "whether it was just for one to reign and another to rule."

753-754 Pope Stephen II crossed alps to ask Peppin for support against the Lombards.

756 Peppin takes the Exarchate of Ravenna from the Lombards and gives it to the Pope.

787 Seventh Ecumenical Council (Nicea II): Dogma of the veneration of icons. Criticized by the Carolingian bishop, Theodulph (in the Libri Carolini).

794-97 Carolingian Councils of Frankfurt and Friuli add "filioque" to Nicene Creed and impose its use in Charlemagne's domain (Rome resists).

800 Charlemagne crowned Roman Emperor (in West) by Pope in Rome and is acclaimed as "Augustus."

808 Pope Leo III writes to Charlemagne that he believes the filioque but that the creed cannot be altered.

c. 860 German mission to the Slavs insists on the filioque, and Pope Nicholas I authorizes them to use it. (A rival mission led by Ss. Cyril and Methodius is allowed not to use it.)

863 Baptism of Boris, Czar of Bulgaria

865 Pope Nicholas I claims authority "over all the earth" and "over every Church."

867 Photius, Patriarch of Constantinople, raises objections to "Filioque."

879 Council of 400 Bishops in Constantinople condemns "Filioque." Council's decision is accepted by Pope John VIII.

1009 Pope Sergius IV uses "filioque" in a letter, and Sergius, Patriarch of Constantinople removes him from the diptychs.

1014 Papacy adopts "filioque" for use in the liturgy on occasion of Henry II's coronation in Rome.

1054 Formal breach between East and West with mutual excommunications between Cardinal Humbert and Patriarch Michael Cerularius. Humbert claims filioque was in the original creed and East removed it.

1100s Crusades introduce a rival Latin jurisdiction into Holy Land.

1190 Theodore Balsamon, Patriarch of Antioch, denies communion to Latins.

1204 Sack of Byzantium by Fourth Crusade (3 times over; only 1/8 left standing). Most of the permanent loss of Greek literature is due to this destruction.

1204-61 Latin Kingdom of Constantinople

1274 Council of Lyons: Filioque and transubstantiation declared dogma in West; failed reunion of Churches

1438-1439 Council of Ferrara-Florence: last attempt at reunion of East and West.