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 uncanonical 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 favourite, 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 saviour but as a peasant adventurer to seize an already sound empire whose next centuries were to be its greatest (see also Eastern Orthodoxy: History). John L. Teall Donald MacGillivray Nicol The Editors of Encyclopaedia Britannica From 867 to the Ottoman conquest The Macedonian era: 867–1025
Under the Macedonians, at least until the death of Basil II in 1025, the empire enjoyed a golden age. Its armies regained the initiative against the Arabs in the East, and its missionaries evangelized the Slavs, extending Byzantine influence in Russia and the Balkans. And, despite the rough military character of many of the emperors, there was a renaissance in Byzantine letters and important developments in law and administration. At the same time there were signs of decay: resources were squandered at an alarming rate; there was growing estrangement from the West; and a social revolution in Anatolia was to undermine the economic and military strength of the empire.
The empire was in theory an elective monarchy with no law of succession. But the desire to found and perpetuate a dynasty was strong, and it was often encouraged by popular sentiment. This was especially true in relation to the Macedonian dynasty, the founder, Basil I, having murdered his way to the throne in 867. Probably of Armenian descent, though they had settled in Macedonia, Basil’s family was far from distinguished and can hardly have expected to produce a line of emperors that lasted through six generations and 189 years. But, having acquired the imperial crown, Basil tried to make sure that his family would not lose it and nominated three of his sons as coemperors. Though he was his least favourite, through the scholarly Leo VI, who succeeded him in 886, the succession was at least secure. Even the three soldier-emperors who usurped the throne during the Macedonian era were conscious, in varying degrees, that they were protecting the rights of a legitimate heir during a minority: Romanus I Lecapenus for Constantine VII, the son of Leo VI; and Nicephorus Phocas and John Tzimisces for Basil II, the grandson of Constantine VII. Military revival
A reassertion of Byzantine military and naval power in the East began with victories over the Arabs by Michael III’s general Petronas in 856. From 863 the initiative lay with the Byzantines. The struggle with the Arabs, which had long been a struggle for survival, became a mounting offensive that reached its brilliant climax in the 10th century. By 867 a well-defined boundary existed between the Byzantine Empire and the territory of the ʿAbbāsid caliphate. Its weakest point was in the Taurus Mountains above Syria and Antioch. Basil I directed his operations against this point, recovered Cyprus for a while, and campaigned against the Paulicians, a Christian sect regarded as heretical by the Byzantines and whose anti-imperial propaganda was effective in Anatolia. But the conflict with Islam was one that concerned the whole empire, in the West as well as in the East, and by sea as well as by land. In 902 the Arabs completed the conquest of Sicily, but they were kept out of the Byzantine province of South Italy, for whose defense Basil I had even made some effort to cooperate with the Western emperor Louis II. The worst damage, however, was done by Arab pirates who had taken over the island of Crete. In 904 they plundered Thessalonica, carrying off quantities of loot and prisoners. Leo VI sent a naval expedition to Crete in 911, but the Muslims drove it off and humiliated the Byzantine navy off Chios in 912.
On the eastern frontier, the Byzantine offensive was sustained with great success during the reign of Romanus I Lecapenus by an Armenian general John Curcuas (Gurgen), who captured Melitene (934) and then Edessa (943), advancing across the Euphrates into the caliph’s territory. It was Curcuas who paved the way for the campaigns of the two soldier-emperors of the next generation. In 961 Nicephorus Phocas, then domestic (commander) of the armies in the West, reconquered Crete and destroyed the Arab fleet that had terrorized the Aegean for 150 years; he thereby restored Byzantine naval supremacy in the eastern Mediterranean. In 962 his strategy achieved unexpected triumphs all along the eastern frontier and culminated in the capture of Aleppo in Syria. When he was proclaimed emperor in March 963, Nicephorus appointed another Armenian general, John Tzimisces, as domestic of the East, though he retained personal command of operations against the Arabs. By 965 he had driven them out of Cyprus and was poised for the reconquest of Syria. The revived morale and confidence of Byzantium in the East showed itself in the crusading zeal of Nicephorus Phocas and John Tzimisces for the reconquest of Syria and the Holy Land. The ground lost to Islam in the 7th century was thus fast being regained; and, although Jerusalem was never reached, the important Christian city of Antioch, seat of one of the patriarchs, was recaptured in 969. These victories were achieved largely by the new cavalry force built up by Nicephorus Phocas. In the areas recovered from the Arabs, land was distributed in military holdings with the interests of the cavalry in mind. But the victories were achieved at the expense of the western provinces, and an attempt to recover Sicily ended in failure in 965.