I'm trying to figure out what place patriarchalism as found in EOy has in OO history.
The sixth canon of Nicaea I appears to evidence the early provincial form of administration by metropolitans: "Let the ancient customs in Egypt, Libya and Pentapolis prevail, that the Bishop of Alexandria have jurisdiction in all these, since the like is customary for the Bishop of Rome also. Likewise in Antioch and the other provinces, let the Churches retain their privileges. And this is to be universally understood, that if any one be made bishop without the consent of the Metropolitan, the great Synod has declared that such a man ought not to be a bishop. If, however, two or three bishops shall from natural love of contradiction, oppose the common suffrage of the rest, it being reasonable and in accordance with the ecclesiastical law, then let the choice of the majority prevail."
The second canon of Constantinople II, however, seems to be beginning to move on to the diocesan form of administration by exarchs, who seemed to have had jurisdiction over numerous metropolitans: "The bishops are not to go beyond their dioceses to churches lying outside of their bounds, nor bring confusion on the churches; but let the Bishop of Alexandria, according to the canons, alone administer the affairs of Egypt; and let the bishops of the East manage the East alone, the privileges of the Church in Antioch, which are mentioned in the canons of Nice, being preserved; and let the bishops of the Asian Diocese administer the Asian affairs only; and the Pontic bishops only Pontic matters; and the Thracian bishops only Thracian affairs. And let not bishops go beyond their dioceses for ordination or any other ecclesiastical ministrations, unless they be invited. And the aforesaid canon concerning dioceses being observed, it is evident that the synod of every province will administer the affairs of that particular province as was decreed at Nice. But the Churches of God in heathen nations must be governed according to the custom which has prevailed from the times of the Fathers." It does explicitly use the word "diocese" rather than "province" or "metropolis". On top of that, "Egypt", "the East", "Asia", "Pontus", and "Thrace" were all among the civil dioceses which were made up of numerous provinces.
It appears that in the 4th century and the first half of the 5th century, the only instances where the jurisdiction of an exarch extended beyond the boundaries of his corresponding civil diocese were in territories outside of the Empire. For instance, at the time when the Catholicos of the Kingdom of Armenia was subject of the Exarch of Caesarea Mazica; and also Egypt's authority over Ethiopia.
The first instance I have found so far of Exarchs actually being given authority beyond the bounds of their corresponding civil diocese was at the Council of Chalcedon. There, the Bishop of Constantinople was not only recognized as having authority over his corresponding Thracian diocese, but also over the Asian and Pontian dioceses. This appears that it may be the first instance of patriarchalism as it later came to be understood in the EO tradition.
On the other hand, I have heard the OO actually rebuked such a move and even restored Ephesus'/Asia's independence from Constantinople at the Third Council of Ephesus.
Is it thus possible that the OO didn't really believe in the concept of patriarchate as it came to be developed by the Byzantines in the Pentarchy?