It is well documented that there was mass persecution by the Byzantine Empire against Non-Chalcedonian communities in the East. Only the Chalcedonian Christianity was legal in the Roman Empire and it was therefore seen as the role of the Roman Empire to remove all influence of what they saw as an illegal Heresy from the Empire.
As Fr Peter Farringdon puts it “By 525 AD the imperial policy was that all resisting monks should be driven out of their monasteries. All over Arabia and Palestine the monks had to leave their monasteries, were robbed, put in irons and subjected to various tortures. Those faithful who gave them shelter were treated in the same way”
The persecution by the Final Byzantine Prefect, El-Moquakas (Later called Patriarch Cyrus of Alexandria), of the Coptic Patriarch Benjamin and others shows the extent of this.
“After the Pope had left Alexandria, the Chalcedonian El-Moquakas arrived, and took charge over the country and the church with authority from Emperor Heraclius. He persecuted the believers and arrested the brother of Abba Benjamin and tortured him severely. He burnt his sides, and finally killed him by drowning.”
Another example comes from the life of St Samuel the Confessor, a monk who refused to accept Chalcedon:
“An envoy came to the desert carrying Leo’s Tome and when the envoy read it to the elders, Abba Samuel became zealous, with the zeal of the Lord. He jumped up in the middle of the gathered monks and seized the letter and rent it into pieces saying, “Excommunicated is this tome and everyone who believes in it and cursed is everyone who might change the Orthodox faith of our Holy Fathers.” When the envoy saw this, he became furious and angry. He ordered him to be beaten with pins and to be hanged up by his arms, and that his face be smitten. One of these strikes enucleated one of St. Samuel’s eyes. Then he was driven away from the monastery.”
Both of these accounts are recorded in the Coptic Synaxarium (Chronicles of the Saints and Martyrs) and read during the Liturgy to remind us of this history. Other examples of attempted forced acceptance byt he state are seen in Jerusalem when Juvenal betrayed his people and accepted Chalcedon, then called the army into the city to stop their protesting.
At the same time, the Syrians had the same situation. A few years ago, HH Patriarch ignatius Zakka of the Syriac Church wrote on the topic, explaining how:
“At the beginning of the 7th century Heraklios (610-641 A.D.) ascended the throne of the East-Roman Empire. After he defeated the Persians and conquered Mesopotamia, he forced his way into Syria in 612 A.D. In 629 A.D. he occupied Damascus. Following that he tried earnestly to restore the religious unity in his empire to unite the Syrians, Copts and Armenians with the Byzantines. This happened on the one hand through promises and on the other hand through threats. Very often he used ruthless oppression through which many Syrians, Copts, and Armenians became martyrs. The persecution of the Syrian Church by the Byzantine Empire did not end until the appearance of Islam.”
He also explains how the Syriac community reacted to the Islamic invasion:
“From the above it becomes clear that the religious conflicts in the Christian church, the attempts of the Byzantine powers to force the issues of the council of Chalcedon upon the other churches by force, to throw its members in prison, to kill them, to ban them and to drive them out alienated the Syrian Christians. All these unchristian deeds only sowed hate and aversion in the hearts of the Syrians against the Byzantine powers. The Persian powers in their empire oppressed both West and East Syrians in general to force them under tyrannical policies and Zoroastrian beliefs. Therefore the Syrians under the Byzantine and Persian powers saw the Islamic conquerors as liberators and not as occupiers. The Syrians put great hope in them, not only because the Muslims liberated them from their religious trouble but also because they relieved the Syrians of the burdensome taxes that were placed on their backs. They said, “Praise be to God, who delivered us from the unjust Byzantines and who put us under the rule of the just Muslim Arabs.”
The Armenian situation was a bit different.Due to Armenia being passed and carved up between the Persian Empire and Rome there was never any chance for any Roman religious authority in the territory.The conflicts between Armenians and Rome during the reign of Justinian had little to do with religion either, so again we see not much evidence of issues outside of land and politics.
Regardless of this, there are times when the state and the Oriental communities were at peace, such as the various rules of Non-Chalcedonian Emperors who allowed religious freedom, as well as Non-Chalcedonian Patriarchs of Constantinople (Anthimus, for example) and Rome who at times implemented policies allowing for freedom. Also the change in the political spectrum at times meant Roman armies needed to work more against Persians and Barbarians than these issues.
One more famous example of peace is the time that Saint Severus of Antioch spent in Constantinople, when he was summoned by Justinian, as Theodora was Non-Chalcedonian. He was welcomed there to help form unity between the two parties (the Constantinople Patriarch was also non-Chalcedonian) and even wrote his famous Hymn ‘O Word Immortal’ (O’ Monogenis) there, though was eventually sent away accused of being a “wolf” demonstrating a continuing division.
So generally, there was a large extent of persecution which continued until the Islamic Conquest. This led to the Syians and Copts welcoming the Islamic invaders as liberators. Other than that, there was not much contact between the two. We see some meeting at the time of the Latin Florentine Council but apart from that, Egypt was too far for the Byzantines to ever visit to any large extent.