Leo OF Saint-.Jeax, a French theologian and con- troversialist, was born at Rennes July 9, IGOO. He en- tered the Carmelite convent when quite young, and, be- ing greatly esteemed by tlie order, he successively tilled nearly all the positions in their gift. He died at the convent "des liillettes," Dec. 30, lti71. He wrote Car- melus restitutus (Par. 1634, 4to) : — Encyclnp. Prcendssum, sell sapient ice universalis delineatio, etc. (1635, 4to) : — Hist. Carmelit. provinci(B Turonensis (1640, 4to). His sermons were published under the title La Somme des Sermons parenetiques et panegijriques (1671-75, 4 vols, fol.). See Hoefer, Nouv. Biorj. Generale, xxx, 738.
Leo Stypiota, or Styppa, or Stypa (SrtVijc)) patriarch of Constantinople in the r2th centurj' (A.D. 1134 to 1143), flourished until about the time of the ac- cession of the Byzantine emperor Manuel Comnenus. A decree of Leo Stypiota on the lawfidness of certain marriages is given in the Jus Orientule of Bonetidus (6£(T/(0( 'Ao\npaTiKoi, Sanction. Pontijic. p. 59), and in the Jus Grwco-Romanum of Leunclavius (liber iii, vol. i, p. 217). He is often cited by Nicolaus Comnenus Po- padopoli. See Fabricius, Bihl. Grcec. viii, 721 ; xi, 606. — Smith, Bict. Greek and Roman Biof/. ii, 745.
Leo OF TiiessalonTca, an eminent Byzantine phi- losopher and ecclesiastic of the 9th century, character- ized by his devotion to learning, studied grammar and poetry at Constantinople, and rhetoric, philosophy, and arithmetic under iVIichael Psellus on the island of An- dros, and at the monasteries on the adjacent part of continental Greece. He afterwards settled at Constan- tinople and became an instructor. Introduced to the notice of emperor Theophilus, he was appointed public teacher or professor, and the Church of the Forty Mar- tyrs was assigned him for a school. Soon after the patriarch John, who appears hitherto to have neglect- ed his learned kinsman, promoted Leo to the archbish- opric of Thessalonica. Upon the death of Theophilus (A.D. 842), when the government came into the liands of Theodora, the iconoclastic party was overthrown, and Leo and .John were deposed Irom their sees; but Leo, whose worth seems to have secured respect, escaped the sufferings which fell to his kinsman's lot; and when Ca'sar Bardas, anxious for the revival of learning, es- tablished the mathematical school at the palace of Mag- naura, in Constantinople, Leo was placed at the head. Leo was still living in A.D. 869; how much later is not known. Symeon {I)e Mich, et Theodora, c. 40) has de- scribed a remarkable method of telegraphic communi- cation invented by Leo, and practiced in the reigns of Theophilus and his son Jlichael. Fires kindled at cer- tain hours of the day conveyed intelligence of hostile incursions, battles, conflagrations, and the other inci- dents of war, from the confines of Syria to Constantino- ple; the hour of kindling indicating the nature of the aceidcnt, according to an arranged plan, marked on the dial-plate of a clock kept in the castle of Lusiis, near Tarsus, and of a corresponding one kept in the palace at Constantinople. The Ms^oOot; npoyi'OfjTiKi], Methodus Prnrpioslicd, or instructions for divining by the Gospel or Psalter, by Leo Saiiiens, in the ]\Iedicean Library at Florence (Bandini, Catedof/. Codd. Laur. Medic, iii, 339), is ijerhaps by another Leo. Combefis was disposed to claim for Leo of Thessalonica the authorship of the cel- ebrated Xpjjffjuoi, Oracula, which are commonly as- cribed to the emperor I^o YI, Sapiens, or the Wise, and have been repeatedly published. But Leo of Thessalo- nica is generally designated in the Byzantine writers the philosopher (0iXoffo0ot-), not the vise (ffo^i'.r) ; and if the published Oracula are a part of the series men-
tioned by Zonaras (xv, 21), they must be older than either the emperor or Leo of Thessalonica. See Fabri- cius, Bibl. Gnecu, iv, 148, 158 ; vii, 697 ; xi, 665 ; Alla- tius. Be Psellis, c. 3-0 ; Labbe, Be Byzant. Histor. Scrip- torihiis nporptTTTiKov, pt. ii, p. 45. — Smith, Bid. ofGrk, ami Rom. Biog. ii, 745 sq.
Leo THE TiiRAciAN (also the Great), or Fla\ti'S Leo I, emperor of Constantinople, was born in Thrace of obscure parents, entered the military' service, and rose to high rank. At the death of the emperor Marcian in A.D. 457, he commanded a body of troops near Selym- bria, and was proclaimed emperor by the soldiers, at" the instigation of Aspar, a Gothic chief, wlio commanded the auxiliaries. The senate of Constantinople confirmed the choice, and the patriarch Anatolius crowned him. This is said to have been the first instance of an emper- or receiving the crown from the hands of a bishop, a ceremony which was aften\-ards adopted by all other Christian princes, and from which the clergy, as Gibbon justlj' observes, have deduced the most formidable consequences. See Investiture. Leo followed the measures of Marcian against the Eutychians, who had been condemned as heretics, and who had recently ex- cited a tumult at Alexandria, had killed the bishop, and placed one iElurus in his stead. Aspar for a time screened ^Elurus; but Leo at last had him exiled, and an orthodox bishop put in his place. The Huns, hav- ing entered the province of Dacia, were defeated by the imperial troops, and a son of Attila was killed in the battle. Soon after, Leo, in concert with Anthemius, emperor of the West, prepared a numerous fleet, with a large body of troops on board, for the recovery of Afri- ca, which was occupied by tlie Vandals. Part of the expedition attacked and took the island of Sardinia ; the rest landed in Libya, and took Tripolis and other towns ; but the delay and mismanagement of the commander, who was Leo's brother-in-law, gave time to Genseric to make his preparations. Coming out of the harbor of Carthage by night, with fire-ships impelled by a fair wind, he set tire to man}^ of the imperial ships, dispersed the rest, and obliged the expedition to leave the coast of Africa. Leo died in January, 474. — Enylish Cyclopit- dia, s. V. ; Smith, Bict. of Greek and Roman Biography and Mythology, ii, 734.