The Council of Nicaea convened to decide the guiding rules of the church - and to resolve the questions posed by Arian theology. A deacon named Athanasius set himself against Arius and succeeded in getting his teachings declared heresy.
the Council of Nicea
What happened at the council of Nicaea? Was the Trinity made up there? Was the divinity of Jesus declared there for the first time? This video answers these question?
The Council of Nicaea. This page from the History Channel offers a neat explanation of the Council, the reasons it was held, the conflicts within it and a brief explanation of the Nicene Creed.
What was the Council of Nicaea? This article lists important figures involved in the Council, as well as describing the factions involved, and their views.