(Μιχαήν), emperor of Constantinople from A. D. 842 to 867, was the son and successor of the emperor Theophilus, and the grandson of Michael II. the Stammerer. He ascended the throne at the age of three, and reigned under the guardianship of his talented mother Theodora. This active princess began by re-establishing the worship of images, an undertaking in which she had to encounter intrigues of a most dangerous nature [PHOTIUS]. Her armies were less successful ; they were beaten in the Caucasus and in Asia Minor, and an expedition fitted out for the recovery of Crete from the Arabs was totally discomfited. She despatched a fleet of 300 ships with a view of conquering Egypt, but the capture and temporary possession of Damietta was the only result of it. On the other hand, she continued to be fortunate in her exertions for the orthodox church and the Christian religion in general: the Khazars were converted in 847, and a few years afterwards the Bulgarians, those hereditary enemies of Byzantium, adopted likewise the religion of Christ [METROPHANES]. But her zeal for images caused a most dangerous revolt of the Paulicians (848), who entered into an alliance with the Arabs, and baffled the efforts of the imperial armies to reduce them to obedience. Meanwhile, Michael grew up and gave proof of his wicked propensities. At the boyish age of fifteen he already led an immoral life with Eudoxia, a noble young lady, the daughter of one Ingerius, who belonged to the great family of the Martinacii; and his mother preferring under these circumstances to give him a lawful wife, he accepted with the greatest indifference Eudoxia, the daughter of Decapolita, continuing all the while his licentious intercourse with the other Eudoxia, his mistress. The principal person at the court was Theoctistus, a celebrated, though not always successful general, who incurred the jealousy of Bardas, the brother of the empress, and the displeasure of the young emperor. Michael and Bardas consequently formed a plot to make away with Theoctistus, and carried their design into effect, Michael being the first to raise his hand against his unfortunate minister. Bardas was appointed Magnus Logotheta in his stead, and he soon seized the uncontrolled direction of public affairs. The murder of Theoctistus so afflicted Theodora that she laid down her functions as regent and retired into private life (854). Michael now abandoned himself to a life of almost unparalleled profligacy, for a description of which we must refer to the graphic pen of Gibbon (vol. ix. p. 45, &c. ed. 1815).

In 856 Bardas was made Caesar; and his power being now unlimited, he caused the empress Theodora, with her daughter, to be confined in a convent. On the whole, however, Bardas was no despicable man, though his ambition was boundless. Full of talents, learning, and an enthusiastic love of the fine arts, he was zealous in promoting the arts, science and literature, which had been greatly neglected during the reign of the father and grandfather of Michael. The philosopher Leo was his principal assistant in attaining these laudable objects. Owing to the irresistible influence of Bardas, the patriarch Ignatius was deposed in 857, and the famous Photius succeeded him. In 858 the empire was involved in a great war with the Arabs. Leo commanded against them, and obtained more glory than the unworthy emperor deserved. He defeated the Arabs in several pitched battles, drove them beyond the Euphrates, crossed that river, and made several successful incursions on the eastern side of the Tigris, penetrating to the neighbourhood of Baghdad. During this time, however, the Arab general, 'Omar, laid Pontus waste. Thinking success on the battle-field an easy thing, Michael resolved to put himself at the head of his army, and marched against 'Omar; but the Arabs had been reinforced by a strong body of incensed Paulicians, and under the walls of Samosata the emperor received a severe lesson for his folly. Upwards of 6000 Greeks were taken prisoners, and among them the gallant Leo, whom the Arabs would never restore to liberty in spite of the brilliant ransom offered them. In 860 Michael paid as dearly for a second lesson in Cappadocia; and 'Omar now carried destruction over Cappadocia, Pontus, and Cilicia, whence he carried 70,000 prisoners into perpetual captivity. (862.) Either good sense or the want of his accustomed revels in the capital, or the advice of Bardas, induced Michael to put his younger brother, Petronas, then governor of Lydia and Ionia, at the head of the army; and Petronas chose for his lieutenant Nazar, governor of Galatia, whose maxim was, that a small, but good army, was better than a large, but bad one. Near Amasia they fell in with the main army of the Arabs, commanded by 'Omar. The Greeks obtained a splendid victory; 'Omar was slain; and his head was carried to Constantinople by Petronas, to whom his brother allowed the honour of a triumphal entrance. In order to commemorate the glory of his armies, and with a view of handing his name down to posterity, Michael ordered a hippodrome to be built, which surpassed everything of the kind in magnificence. Jealous of Petronas, the emperor set out in 864 for the purpose of taking the command. He had scarcely arrived in Asia when he was recalled, because a Russian fleet of 200 large barges had suddenly made its appearance in the Bosporus, and was attacking the Golden Horn. Michael hardly escaped being taken prisoner whilst crossing the Hellespont, but he was soon released from his fear, in consequence of the Russian fleet being destroyed by storm. This was the first blockade of Constantinople by the Russians, or, more correctly speaking, by the Norman nobles, who had just made themselves masters of Western Russia. By this time Michael had grown tired of the ascendancy of Bardas, and felt deeply offended at being exhorted by him to lead a better life. Whether Bardas meant this in reality or not is a matter of doubt, for he certainly wished to establish his own elevation on the ruin of Michael. Bardas was thus gradually superseded in the favour of his master by Basil the Macedonian, afterwards emperor, who married Michael's mistress, Eudoxia, in exchange for whom he surrendered his sister, Thecla, who became the emperor's mistress. Michael formed a plot with Basil to assassinate Bardas; and soon afterwards the Caesar was treacherously killed by Michael, Basil, and a band of assassins hired for the purpose (866). Thereupon Basil rose to eminence, and was proclaimed Caesar. In the same year (866) the patriarch Photius proclaimed the deposition of pope Nicholas I. The conduct of Michael continued to be so disgusting, that Basil. in his turn, remonstrated with him, and soon incurred the hatred of his master, who began to look out for some daring men who would help him in despatching the Macedonian. Of this Basil became informed, and very naturally resolved to anticipate the emperor's designs. le persuaded him to accept a supper in the house of his mother, Theodora, who, utterly unacquainted with the intention of Basil, had consented to invite her son, as a means of restoring a good understanding between the relers. As the supper degenerated into an orgy, Theodora and her daughter retired, leaving her son alone with Basil and a few more guests, who soon made the emperor so drunk, that he was obliged to lie down on a bed. In this helpless state he was murdered by a band of assassins who had been secretly introduced into Theodora's dwelling. (24th of September, 867.) Basil followed him on the throne. The reign of Michael III., however disgusting the part which he played, is one of the most interesting in Byzantine history: it is rich in events worthy of the attention of the scholar, the philosopher, the historian, the soldier, and the divine; and whoever feels more than superficial sympathy for the fate of the later Greeks will be amply rewarded by turning from this imperfect sketch to the sources from which it is taken. (Cedren. p. 533, &c.; Zonar. vol. ii. p. 152, &c. ; Leo (Gram., p. 457, &c.; Symeon Metaphrast., p. 428, &c.; Theophan. Contin. p. 92, &c.; Genes. p. 37, &c.; Joel, p. 179, &c.; Const. Manass. p. 100.)