Chalcedon, Council of: The Fourth Ecumenical Council, held in 451, from 8 October until 1 November inclusive, at Chalcedon, a city of Bithynia in Asia Minor.
Constantinople, First Ecumenical Council of: Called in May, 381, by Emperor Theodosius, to provide for a Catholic succession in the patriarchal See of Constantinople, to confirm the Nicene Faith, to reconcile the semi-Arians with the Church, and to put an end to the Macedonian heresy.
Ephesus, Council of: The third ecumenical council, held in 431.
First Council of Constantinople - 381: Introduction to the council and its historical setting, with text of its decisions.
First Council of Nicea - 325 AD: Introduction to the council and its historical setting, with text of its decisions.
Medieval Sourcebook: Full Text Sources:
Nicaea, First Council of: First Ecumenical Council of the Catholic Church, held in 325 on the occasion of the heresy of Arius. It defined the Nicene Creed.
Nicaea, Second Council of: A council that was called to deal with the heresy of Iconoclasm.
Second Council of Constantinople - 553 A.D.: Introduction to the council and its historical setting, with text of its decisions.
Second Council of Nicaea - 787: Introduction to the council and its historical setting, with text of its decisions.
The Council of Chalcedon - 451 A.D.: Introduction to the council and its historical setting, with text of its decisions.
The Council of Ephesus: A set of texts produced by this "robber's council".
The Council of Nicaea: A Protestant view of this first council.
The Seven Ecumenical Councils of the Undivided Church: Interpretations of the documents by Protestant historian Philip Schaf. From Christian Classics Etheral Library.
Third Council of Constantinople : 680-681 A. D.: Introduction to the council and its historical setting, with text of its decisions.