surnamed SA'PIENS and PHILO'SOPHUS, emperor of Constantinople (A. D. 886-911), second son of Basil I., the Macedonian, by his second wife, Eudoxia, was born in A. D. 865, and succeeded his father on the 1st of March, 886, after having previously been created Augustus. A short time before the death of Basil, young Leo narrowly escaped the punishment of a parricide, a crime, however, of which he was not guilty, but of which he was accused by the minister, Santabaren, the knavish favourite of the emperor. As soon as Leo ascended the throne he prepared for revenge. He began by deposing the notorious patriarch Photius, who was the chief support of Santabaren; and having got rid of that dangerous intriguer, he had the minister arrested, deprived him of his eyes, and banished him to one of the remotest corners of Asia Minor. The reign of Leo presents an uninterrupted series of wars and conspiracies. In 887 and 888 the Arabs invaded Asia Minor, landed in Italy and Sicily, and plundered Samos and other islands in the Archipelago: it was only in 891 that the emperor's authority was re-established in his Italian dominions. Styiianus, Leo's father-in-law, and prime minister, gave occasion to a bloody war with the Bulgarians. At that period these people were no longer so barbarous as in former centuries, and they carried on a considerable trade with the Byzantine empire, having their principal factories at Thessalonica, where they enjoyed great privileges. These privileges Stylianus disregarded, and exposed the Bulgarian merchants to vexations and ill-treatment. Thence arose a war with the Bulgarian king, Simeon, who ravaged Macedonia, and routed the Greek army, commanded by Leo Catacalon and Theodosius, the latter of whom was killed in the action, to the great regret of the nation and the emperor. The credit of Stylianus ceased with the death of his daughter, the empress; and his disgrace grieved him so much that he died of sorrow and disappointed ambition (894). Leo got rid of the Bulgarians by involving them, through intrigues, in a war with the Hungarians. The following years were rendered remarkable by several conspiracies. That of 895 proved nearly fatal to the emperor, but it was discovered in time, and quelled by one Samonas, who, in reward, was created patricius, and soon rose to great wealth and power. A few years afterwards Leo was attacked in a church during service by a ruffian, who felled him to the ground with a club; but on this occasion also the emperor escaped, and the assassin met with the fate he deserved. The inactivity of Leo induced the Arabs and northern neighbours of the empire to attack it at their convenience. The former once more invaded Sicily, and took Tauromenium; and in 904 appeared with a numerous fleet in the harbour of Thessalonica. This splendid city, the second in wealth and population after Constantinople, was ill fortified and still worse garrisoned, so that in spite of the efforts of the inhabitants, the Arabs soon made themselves master of it. They destroyed a great portion of it; and after having plundered it during ten days, left the harbour with their fleet laden with booty and captives. The history of this conquest was described by Joannes Cameniata in his valuable work, The Capture of Thessalonica (Ἠἅλωσις τῆς Θεσσαλονίκης). [CAMENIATA.] About this time the last remains of the authority of the senate were finally abolished by a constitution of Leo. In 910 Samonas was sentenced to perpetual imprisonment for having abused the confidence the emperors had never ceased to bestow upon him since he had crushed the conspiracy of 895. In 911 the Arabs defeated the Greek fleet off Samos. In this action the Greeks were commanded by Romanus Lecapenus, who became emperor during the minority of Constantine VII. Porphyrogenitus. Leo died in the same year, 911, either on the 11th of May or on the 11th of July, of a chronical dysentery. His successor was his infant son, Constantine Porphyrogenitus, whom he had by his fourth wife, Zoe; and his younger brother, Alexander, who had nominally reigned with Leo since the death of their father, Basil, but who, preferring luxury and idleness to business, had abandoned his share in the government to his elder brother Leo. Leo was married four times; in consequence of which he was excluded from the communion with the faithful by the patriarch Nicolaus, as the Greek church only tolerated a second marriage: it censured a third, and it condemned a fourth as an atrocious sin. The first wife of Leo was Theophano, the daughter of Constantinus Martinacius; the second Zoe, the widow of Theodorus Guniatzita, and the daughter of the minister Stylianus, who, after the marriage of Zoe, received from his son-in-law the unusual title of basileopator, or father of the emperor; the third was Eudoxia, a woman of rare beauty; and the fourth was Zoe Carbonopsina, who survived her husband.

It is difficult to understand how the exalted name of Philosophus could be given to a man like Leo, and one would feel inclined to take it ironically, were it not for the impudent flattery of the later Greeks. Gibbon, with a few striking words, gives the following character of this emperor: -- "The name of Leo VI. has been dignified with the title of philosopher; and the union of the prince and the sage, of the active and speculative virtues, would indeed constitute the perfection of human nature. But the claims of Leo are far short of this ideal excellence. Did he reduce his passions and appetites under the dominion of reason? His life was spent in the pomp of the palace, in the society of his wives and concubines; and even the clemency which he showed, and the peace which he strove to preserve, must be imputed to the softness and indolence of his character. Did he subdue his prejudices, and those of his subjects? His mind was tinged with the most puerile superstition; the influence of the clergy, and the errors of the people, were consecrated by his laws; and the oracles of Leo, which reveal in prophetic style the fates of the empire, are founded on the arts of astrology and divination. If we still inquire the reason of his sage appellation, it can only be replied, that the son of Basil was less ignorant than the greater part of his contemporaries in church and state; that his education had been directed by the learned Photius; and that several books of profane and ecclesiastical science were composed by the pen, or in the name of the imperial philosopher."