Under Constantine V, the struggle against the icons became a struggle against their chief defenders, the monastic community. The immediate destruction wrought by Constantine and his zealous subordinates is, however, of less moment than the lasting effect of the persecution on the Orthodox clergy. Briefly put, the church became an institution rent by factions, wherein popular discontent found a means of expression. Intransigent iconodules looked for their leaders among the monks of Studion, the monastery founded by Studius, and they found one in the person of the monastery’s abbot, St. Theodore Studites (759–826). In the patriarch Ignatius (847–858; 867–877) they discovered a spokesman after their own hearts: one drawn from the monastic ranks and contemptuous of all the allurements that the world of secular learning seemed to offer. More significant than the men to be found on the other extreme, iconoclast patriarchs, including Anastasius and John Grammaticus, were the representatives of the moderate party, composed of the patriarchs Tarasius, Nicephorus, Methodius, and Photius. Although iconodule in sympathy, the group enjoyed little rapport with the monastic zealots. Unlike the average monk, they were often educated laymen, trained in the imperial service and ready to compromise with imperial authority.
Not only was Iconoclasm a major episode in the history of the Byzantine, or Orthodox, Church, but it also permanently affected relations between the empire and Roman Catholic Europe. The Lombard advance, it may be remembered, had restricted Byzantine authority in Italy to the exarchate of Ravenna, and to that quarter the popes of the 7th century, themselves ordinarily of Greek or Syrian origin, turned for protection against the common enemy. During the 8th century, two issues alienated Rome from Constantinople: Iconoclasm and quarrels stemming from the question of who should enjoy ecclesiastical jurisdiction over Illyricum and over Calabria in southern Italy. Pope Gregory II refused to accept the iconoclastic doctrines of Leo III, and his successor, Gregory III, had to openly condemn them at a council. Once Ravenna fell to the Lombards, and the exarchate ceased to exist in 751, the papacy had to seek a new protector. That was found in the person of the Frankish leader Pippin III, who sought some form of sanction to legitimize his seizure of the crown from the feeble hands of the last representative of the Merovingian dynasty.
Thus, Pope Stephen II (or III) anointed Pippin as king of the Franks in 754, and the latter entered Italy to take arms against the Lombard king. Even the restoration of icon veneration in 787 failed to bridge the differences between Orthodox Byzantium and Catholic Europe, for the advisers of Pippin’s son and successor, Charlemagne, condemned the iconodule position as heartily as an earlier generation had rejected the iconoclast decrees of Leo III. Nor could the men of Charlemagne’s time admit that a woman—the empress Irene—might properly assume the dignity of emperor of the Romans. For all those reasons, Charlemagne, king of the Franks and Lombards by right of conquest, assented to his coronation as emperor of the Romans on Christmas Day, 800, by Pope Leo III. No longer had a barbarian king, Charlemagne become, by virtue of the symbolism of the age, a new Constantine.
This the Byzantine chancery could not accept, for, if there were one God, one faith, and one truth, then there could be but one empire and one emperor; surely that emperor ruled in Constantinople, not in Charlemagne’s Aachen. Subsequent disputes between Rome and Constantinople seemed often to centre on matters of ecclesiastical discipline.
Underlying those differences were two more powerful considerations, neither of which could be ignored. According to theory, there could be but one empire; clearly, there were two. And between Rome and Constantinople there stood two groups of peoples open to conversion: the Slavs of central Europe and the Bulgars in the Balkans. From which of the two jurisdictions would those people accept their Christian discipline? To which, in consequence, would they owe their spiritual allegiance?
The reign of Michael III (ruled 842–867) draws together those and other threads from the past. Veneration of the icons was definitely rehabilitated in 843, and it was done in so diplomatic a fashion that the restoration, in itself, produced no new rifts, although old factionalisms persisted with the appointment of a monk, Ignatius, as patriarch.
The latter’s intransigent zealotry found little favour with Caesar Bardas, Michael’s uncle, who had seized power from the empress regent in 856. Two years later Ignatius was deposed and replaced by a moderate: the scholar and layman Photius. No single person better exemplified the new age, nor, indeed, did any other play a larger part in the cultural rebirth and missionary activity among the Slavs, Bulgars, and Russians, which mark the middle of the 9th century. The same aggressive and enterprising spirit is manifest in the military successes won on the Asia Minor frontier, culminating in Petronas’s victory at Poson (863) over the Muslim emir of Melitene.
In Sicily and throughout the Mediterranean, Byzantine arms were less successful, but, thanks to Photius’s diplomatic skill, the see of Constantinople maintained its position against Rome during the so-called Photian Schism.
When Pope Nicholas I challenged Photius’s elevation to the patriarchate, deploring as uneconomical the six days’ speed with which he had been advanced through the successive ranks of the hierarchy, the Byzantine patriarch refused to bow. He skillfully persuaded Nicholas’s delegates to a council summoned at Constantinople to investigate the matter that he was the lawful patriarch despite the persisting claims of the rival Ignatian faction.
Nicholas, alleging that his men had been bribed, excommunicated Photius; a council at Constantinople responded (867) by excommunicating Nicholas in turn. The immediate issues between the two sees were matters of ecclesiastical supremacy, the liturgy, and clerical discipline; behind those sources of division lay the question of jurisdiction over the converts in Bulgaria.
And behind that question may be found centuries of growing separation between the minds and institutions of the eastern and the western Mediterranean worlds, symbolized in the roles assumed by two among the major protagonists in the Photian Schism. It was the supreme spiritual authority, the pope, who hurled anathemas from the West, but it was God’s vicegerent on earth, the emperor Michael III, who presided at the council of 867.
Michael did not long survive that moment of triumph. Later that year he was murdered by his favorite, Basil, who, on his bloody path to the throne, had earlier disposed of Caesar Bardas. As had Heraclius and Leo III before him, Basil came to found a dynasty, in this instance the Macedonian house. Unlike his predecessors, he came not as a savior but as a peasant adventurer to seize an already sound empire whose next centuries were to be its greatest.