First let us get out of the way the belief that Arius was the originator of the Heresy that bears his name. Let us look at the forerunners of that Heresy.
The First to deny that Christ was God was Theodotus the Leather-Dealer. Pope St. Victor excommunicated Theodotus calling Christ a mere MAN. (Circa 190 A.D.)
There was much Theological debates about the true Nature of Christ as God. How was he God? Was he God as the Father is God?
Sabellius an African denied that there were 3 Distince persons in God. He and his Followers believed that the three persons were like stage characters, representing the Godhead at different times to Men. This was rejected by the whole Church because it was clearly contrary to scripture and tradition.
St. Dionysius of Alexandria made an error when he stated that the Son was "Made by God" as if he hadn't always existed and was subordinate to him. Though not his intention he did what Justin Martyr and Origen had done before him. This of course was simple error on their parts.
When Pope Dionysius found out what St. Dionysius had said he quickly stated in a document to the Bishops in Alexandria.
"Had the Son been created, there would have been a time when he was not; but the son always was."
Thereupon the Bishop of Alexandria explained away his previous inaccurate language and distinctly confessed the Son's eternity.
This was all in the 3rd Century, about the same time, Paul of Samosata Bishop of Antioch taught that Christ was not the real but adopted Son of God. He was condemned and deposed by a Council of Bishops which met at Antioch in 269 A.D.
Paul of Samosata was a Heretic because he taught a false Doctrine and OBSTINATLELY persisted in holding it even after it had been condemned by the Church.
Obstinancy is the distinctive note of the Heretic, St. Dionysus was not a heretic.
Now we're getting closer, Lucian was taught by Paul of Samosata, he founded a great school of Theology and Holy Scripture at Antioch.
He got many of his ideas from his former master. Lucian believed that the Son was subordinate to the Father and was neither perfect God nor perfect man.
Lucian died a Martyrs death in 311 A.D.
Two of Lucians most noted students were Eusebius of Nicomedia and ARIUS of Egpyt.
Arius was still a Layman or at most in Minor Orders when he settled down in Alexandria in the first decade of the fourth century. Bishop Peter of Alexandria raised Arius to the deaconship but was forced to Excommunicate him soon afterwards for supporting a schismatic party called the Meletians after the Egyptian Bishop of that name. Peter was Martyred in 311. He was succeeded by Achillas as Bishop. Achillas not only freed Arius from excommunication but he ordained him to the Priesthood and put him in charge of one of the grandest Churches in the City.
Alexander succeded Achillas and held Arius in high repute until suddenly at a Clerical Conference around 318 Arius threw off the mask and revealed his true character. He had been informed that erroneous opinions had been floating around the city regarding the Trinity and that Arius was one of the Chief offenders. I won't speak Heresy by stating what Arius said in his "Defence" but it was not good. Alexander set forth the True Doctrine and commanded Arius to retract his blashemous assertions. Deeply wounded in his pride the book "Church History" by Father John Laux M.A. states, that Arius persisted in his error. He accoused his Bishop of being a Gnostic and a Sabbellian and posed as the champion of pure doctrine against heresy. As the book later states
"Blinded by his obstinancy, he did not see that his own brand of monotheism 'was hardly to be distinguished from that of the pagan philosophers, and that his Christ was nothing but a Greek demi-god'"
At this time Arius wrote to Bishops in Greeece and Asia Minor who like him had passed through the school of Lucian. He asked them to examine his enclosed profession of faith and to intercede for him in with Alexander. The most influential of his friends was the aforementioned Eusebius who by now was the Bishop of Nicomedia. He was also a kinsmen of the Emperor. Arius rightly held hopes that Eusebius would defend him and he was not disappointed. Eusebius set about trying to win as many Bishops as he could for his old school fellow. What had started off as a minor controversy was now an affair that concerned the whole empire. 9 Bishops 2 of which were suffragens of Alexandria, 7 Priests, and 12 Deacons openly sided with Arius, aswell as 700 Concecrated Virgins.
Alexander too was active, when he saw that bringing Arius to his senses was hopeless, he called a Synod in 320 A.D.
Nearly 100 Bishops responded and unanimously anathematized Arius and his adherents. Still Arius would not submit. He continued his propoganda more vigorously then ever, and even went so far as to arouse the pagan rabble of the city against his opponents. Alexander then called another synod which by a circular letter made known the Excommunication of Arius and his followers to all the Bishops of the world.
Arius now left Egypt and went to Palestine where he decieved a few Bishops then he went Nicomediathe reisddence of his powerful friend Eusebius. He then wrote a book, intended for the common people to convert them to his heresy.
When Licinius renewed the persecutions of the Christians in the easy, Arius used that to his advantage to get back to Alexandria.
Licinius was defeated in 323 and Constantine was now sole Emperor of the Empire.
Through Hosius Bishop of Cordova who was an adviser to Constantine, he decided to end the divisive split that was occuring in his empire. He summoned both Alexander and Arius to end their quarrelling 'over and issue only a few understand anyway'(I paraphrased it, but that is the gist of it) This came to nothing and on the advice of Hosius and with the active concurrance of Pope Sylvester Constantine called a council at the Imperial Palace at Nicea in Bithnyia for all the Bishops of the Church to attend.
The First Ecumenical Council of Nicea started on May 20th 325 A.D.
250 Bishops attended, but before it had finished it's last session this number rose to 318. Each Bishop was attended by 2 Priests or Deacons and in many cases several clerics of lower rank. These took no active part in the deliverations of the Council, but some of them especially Athanasius the archdeacon of Alexandria were prominent in private conferences and semi-public disputations.
Bishops were there from all over, but alas the Pope Sylvester was not able to come due to his old age. Hosius of Cordova acted as Legate of the Pope. and the Roman Priests Vitus and Vincent -precursors of the later cardinals- presided at the Council.
I am not going to give a complete history of Nicea, but it was not a peaceful council, many remarks were scandalous and hateful.
As everyone should know the end result was the Nicene Creed. The Creed was signed by all but 2 Bishops. Theonas of Marmarica and Secundus of Ptolemais.
Both of them along with Arius were Exiled by the Emperor to Illyria.
Three months after the Council Eusebius of Nicomedia and Theognis of Nicea were also Banished because in spite of their signature they refused to recognize the condemnation of Arius, gave hospitatlity to Arians and openly professed Arian errors.
Constantia, the sister of Constantine and widow of Licinius had been an ardent follower of Arius from the very beginning. Her adviser in all spiritual matters had been Eusebius of Nicomedia. Through intrigue her and her new adviser(an Arian whose name is not on record) managed to put doubt into Constantines mind stating things such as "Arius was condemned because of a conspiracy it was all because they didn't like him and that he wasn't a heretic at all" and such other nonsense.
Eusebius and Theognis were recalled from exile and restored to their Sees.
Eusebius now thirsting for revenge organised the Arian reaction.
I am getting tired, so maybe I'll finish this tommorow, so noone is in real suspense the next part is basically Arius is removed from exile and is ordered to have his previous position back. St. Athansius is now by this time now the Bishop of Alexandria(Patriarch of the Coptic Rite) and says "uh NO!"