"The Arian heresy [...] divided the church for over sixty years. It stubbornly survived the Council of Nicea in 325 CE which had been called to settle the issue of the relationship of Christ to God Father. It was not put to rest until Constantinople in 381. Basil, the great Cappadocian, describes the bitterness of the struggle by portraying it as a fraticidal battle which was destroying the church." (146)
See Athanasius' Four Discourses Against the Arians
Arians deny "the Son's co-eternity with the Father"... Christ has a "creaturely status" which is important, but which forecloses the possibility of "full divinity"
Sophia gets caught up in the Arian heresy -- see separate note elsewhere