Today in the Middle Ages: June 19, 325

The Emperor Constantine convened the first Council of Nicea on June 19, 325.

The Council was the first attempt to establish a consensus among all Christian bishops on a point of doctrine: the nature of Christ the Son's oneness with God the Father. The delegates rejected the Arian doctrine, and Arius himself, who was in attendance, was disgraced. An early version of the Nicene Creed was agreed upon by almost all present.

The Council also determined to set the date of Easter from the vernal Equinox, disconnecting it from the Jewish Passover.