Leo III

Leo III, Byzantine emperor

Leo III (Leo the Isaurian or Leo the Syrian), c.680–741, Byzantine emperor (717–41). He was probably born in N Syria (rather than in Isauria, as once thought). He held diplomatic and military posts before he deposed and succeeded Theodosius III. His accession ended the anarchy into which the empire had fallen since the reign of Justinian II. Leo defended Constantinople against the last Arab siege (717–18), and although he had to contend with Arab attacks in Asia Minor, he succeeded in ending serious Arab threats for nearly two centuries and reorganized the military provinces (themes) of the empire for greater efficiency. His civil code, the Ecloga, written in Greek rather than in Latin, was a practical handbook that had considerable influence in Byzantium. He is also credited with issuing military, maritime, and rural codes. Leo's attack (726) on devotion to holy images began the long struggle over iconoclasm. Riots and rebellions broke out in Greece, while Byzantine rule in Italy (the exarchate of Ravenna and the Pentapolis of Rimini, Ancona, Fano, Pesaro, and Senigallia) began to crumble. The popes Gregory II and Gregory III opposed Leo's iconoclasm and successfully defied his armed expeditions, thus virtually ending Byzantine suzerainty over Rome. Nevertheless, Leo left a revitalized empire to his son, Constantine V. The Isaurian, or Syrian, dynasty, which he founded, ruled the Byzantine Empire until 802.

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Leo III

 known as Leo the Isaurian

(born c. 675, Germanicia, Commagene, Syria—died June 18, 742, Constantinople) Byzantine emperor (717–41), founder of the Isaurian dynasty. A high-ranking military commander, he seized the throne with the help of Arab armies who hoped to subjugate the Byzantine Empire. He then successfully defended Constantinople against the Arabs (717–718). Having crowned his son Constantine V coemperor (720), Leo used his son's marriage to cement an alliance with the Khazars. Victory over the Arabs at Akroïnos (740) was crucial in preventing their conquest of Asia Minor. Leo issued an important legal code, the Ecloga (726). His policy of iconoclasm (730), which banned the use of sacred images in churches, engendered a century of conflict within the empire and further strained relations with the pope in Rome.

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Leo III

1. called the Isaurian. ?675--741 ad, Byzantine emperor (717--41): he checked Arab expansionism and began the policy of iconoclasm, which divided the empire for the next century

2. Saint. ?750--816 ad, pope (795--816). He crowned Charlemagne emperor of the Romans (800). Feast day: June 12