Representatives came from across the Empire, subsidized by the Emperor.
The council drew up a creed, the original Nicene Creed, which received nearly unanimous support.
The council's description of "God's only-begotten Son", Jesus Christ, as of the same substance with God the Father became a touchstone of Christian Trinitarianism.
Emperor Constantine convened this council to settle a controversial issue, the relation between Jesus Christ and God the Father.
The Emperor wanted to establish universal agreement on it.
For those who accept it (Eastern Orthodox, Roman Catholics, and most Protestants), it is the Fourth Ecumenical Council (calling the Second Council of Ephesus, which was rejected by this council, the "Robber Synod" or "Robber Council").
In November 448, a synod at Constantinople condemned Eutyches for unorthodoxy.
The opponents of Arianism rallied, and the First Council of Constantinople in 381 marked the final victory of Nicene orthodoxy within the Empire, though Arianism had by then spread to the Germanic tribes, among whom it gradually disappeared after the conversion of the Franks to Christianity in 496. 4) recorded Alexandrian scribes around 340 preparing Bibles for Constans.
In 331, Constantine I commissioned Eusebius to deliver fifty Bibles for the Church of Constantinople. Little else is known, though there is plenty of speculation.
There is also one additional council (the Quinisext Council), which was held between the sixth and seventh Ecumenical Councils (in A. 692), and which issued organizational, liturgical and canonical rules but did not discuss theology.