Fourth Ecumenical Council

Council of Chalcedon
Fourth Ecumenical Council of Chalcedon, 1876 painting by Vasily Surikov
Date	AD 451
Accepted by	Roman Catholics, Old Catholics, Eastern Orthodox, Anglicans, Lutherans and most other Protestants
Previous council	Council of Ephesus
Next council	Second Council of Constantinople
Convoked by	Emperor Marcian
President	Anatolius, Patriarch of Constantinople; A board of government officials and senators, led by the patrician Anatolius
Attendance	Approx. 520
Topics	the judgments issued at the Second Council of Ephesus in 449, the alleged offences of Bishop Dioscorus of Alexandria, the definition of the Godhead and manhood of Christ, many disputes involving particular bishops and sees
Documents and statements	Chalcedonian Creed, 28 canons
Chronological list of Ecumenical councils

The Council of Chalcedon (/kælˈsiːdən/ or /ˈkælsᵻdɒn/) was a church council held from October 8 to November 1, AD 451, at Chalcedon. The Council is numbered as the fourth ecumenical council by the Great Church. A minority of Christians do not agree with the council's teachings. Its most important achievement was to issue the Chalcedonian Definition. The Council's judgments and definitions regarding the divine marked a significant turning point in the Christological debates. Chalcedon was a city in Bithynia, on the Asian side of the Bosphorus; today the city it is part of the Republic of Turkey and is known as Kadıköy (a district of Istanbul).

The Council of Chalcedon was convened by Emperor Marcian, with the reluctant approval of Pope Leo the Great, to set aside the 449 Second Council of Ephesus which would become known as the "Latrocinium" or "Robber Council". The Council of Chalcedon issued the Chalcedonian Definition, which repudiated the notion of a single nature in Christ, and declared that he has two natures in one person and hypostasis. It also insisted on the completeness of his two natures: Godhead and manhood. The council also issued 27 disciplinary canons governing church administration and authority. In a further decree, later known as canon 28, the bishops declared that the See of Constantinople (New Rome) was, in honour, second only to the See of Rome.