c. 318–325

The Beginning of the Arian Controversy: Arius and Alexander of Alexandria

Arius, a presbyter of Alexandria, was formed by Origen's subordinationism and was apparently a student of Lucian of Antioch. He put forward a teaching of the Son as created and not of one substance with the Father. Bishop Alexander of Alexandria opposed him, supported by the deacon Athanasius. Alexander convened councils in Alexandria attended by up to a hundred bishops and circulated letters defending orthodoxy.

The excommunicated Arius found support among a number of "fellow Lucianists", chiefly Eusebius of Nicomedia and, in part, Eusebius of Caesarea. The dispute began as a local one but grew into a conflict engulfing the whole East. In early 325 a local council at Antioch pre-emptively condemned Arian formulas. This prepared the ground for the Council of Nicaea.