Arianism is the name given to a complex development in the 4th century in ecclesiastical, intellectual and political history. The founder of this movement, Arius (d. 336), was an Alexandrian presbyter, formerly of the Antiochene circle of the Syllucianists. His intellectual forebears were the Antiochene Adoptionists, Paul of Samosata and Lucian. Aetius of Antioch and Eunomius of Cyzicus gave an extreme form to the theology of Arius.

Arianism, together with its Athanasian and early Nicaean counterparts, marked the end of an epoch in Christian thought which centr…