(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