First Council of Nicaea

=== Before Nicaea ===
In the first place, Constantine legalized Christianity. During the first three centuries, the Roman authorities persecuted Christianity. The [[Diocletianic Persecution]] of 303-313 was the most severe persecution of Christians up to that point in history. Diocletian's first edict commanded churches and holy sites razed to the ground, sacred articles burned, and believers jailed. However, in 313, the Western Roman Emperor Constantine (306–337) legalized Christianity through the Edict of Milan. He granted Christians "the right of open and free observance of their worship."

“In 324 the Emperor Constantine … (who recently) assumed control of the whole empire, took an interest in the dispute. Constantine wrote to Alexander and Arius telling them to stop quarrelling about what seemed to him to be such a small matter.”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 17-18</ref> Constantine wrote:<blockquote>“For as long as you continue to contend about these small and very insignificant questions, I believe it indeed to be not merely unbecoming, but positively evil, that so large a portion of God’s people which belong to your jurisdiction should be thus divided.”<ref>Davis, Leo Donald. The First Seven Ecumenical Councils (325-787): Their History and Theology. Vol. 21. Collegeville, Minn: Liturgical Press, 1990. 55</ref></blockquote>Constantine, therefore, attempted to intervene even before he understood what this dispute was about. “It initially took the efforts of bishops like Ossius and Alexander of Alexandria to persuade him that anything significant was at issue in Alexandria.”<ref>Ayres, Lewis, Nicaea and its Legacy, An Approach to Fourth-Century Trinitarian Theology, 2004, page 87-88</ref>

A few months before the Council of Nicaea, “early in 325,” an “anti-Arian Council”<ref>Hanson RPC, page 131</ref> was held in Antioch,<ref>Hanson RPC, page 149</ref> consisting mainly of those who sympathized with Alexander.<ref>Hanson RPC, page 130</ref> “In normal circumstances the Metropolitan of the area in which the Council met would have presided … But Constantine's representative, Ossius, took precedence … over Eustathius.”<ref>Hanson RPC, The Search for the Christian Doctrine of God: The Arian Controversy, 318-381. 1988, page 155</ref> Ossius was “the Emperor's representative”<ref>Hanson, 154</ref> and Constantine’s “agent.”<ref>Hanson, 190</ref> He was “Constantine's chief adviser and agent in matters concerning the Christian church.”<ref>Hanson, 130</ref> This implies that the meeting took place with the approval of the emperor, which means that, even before Nicaea, "Constantine had taken Alexander's part"<ref name=":1"/> in his dispute with Arius.