The First Council of Nicaea occurred in 325, convened by Constantine I to solve problems raised by Arianism. The council adopted a formula based on a simple baptismal creed to test faith of the attendees. It is not the Nicene Creed as is known today, however. It was accepted by all bishops but two, and they were banished to Illyricum. They worked to standardize the date of Easter and is the model for great councils. It proved a universal statement of faith in place of earlier varying baptismal formulas and is very important in the history of the Christian church.