05 The Council of Nicaea

In 325 the Emperor Constantine called a meeting of Christian leaders in the city of Nicaea. At the Council of Nicaea a fierce debate took place over the meaning of Christianity. Ultimately the Council adopted the trinitarian doctrine of Christianity. Once Christianity was defined it was adopted as the official religion of the Roman Empire. Dissident churches remained including Christians in Syria, Egypt and a faction led by a bishop named Arius in France.