Four æcumenical councils held in the capital of the former Byzantine Empire. Their principal acts of these Councils were disciplinary and dogmatic.
The First Council of Constantinople in 381 condemned Arianism, Macedonianism, and kindred heresies. It formally approved of the Nicene-Constantinopolitan Creed.
The Second Council of Constantinople in 553 anathematized the , and issued dogmatic condemnations against Arius, Nestorius, and other heretics.
The Third Council of Constantinople in 618 defined the Church‘s doctrine on the two wills (human and Divine) in Christ, at the same time anathematizing the opposite (Monothelitic) heresy.
The Fourth Council of Constantinople in 869 condemned Photius and the acts of the false Photian councils.