Leo the ruler
Leo, the name of six rulers of the Byzantine, or Eastern Roman, Empire.
Leo I(400?–474), called the Great by his friends and the Butcher by his enemies, ruled 457–74. An expedition he launched against the Vandals in Africa ended in disaster.
Leo II(467?–474) was Leo I's grandson. He outlived Leo I by only a few months.
Leo III(680?–741), called the Isaurian, ruled 717–41. (Isauria was the ancient name of a region in present-day Turkey.) Leo came to power while the Saracens were attacking Constantinople (Istanbul). Under his leadership the enemy was defeated. Leo issued a decree forbidding the worship of icons (religious images). The decree worsened relations with the papacy and led to revolts in Byzantine provinces in Greece and Italy. Leo strengthened the empire by his civil and military reforms.
Leo IV(750?–780) ruled 775–80. He was the grandson of Leo III. Near the end of his short reign Leo resumed efforts to end icon worship.
Leo V(?–820), called the Armenian, ruled 813–20. Leo successfully waged war against the Bulgars to the north. He opposed the use of images in the churches and was murdered by religious enemies.
Leo VI(866–912), called the Philosopher, ruled 886–912. Sicily, which had been under Byzantine rule, was lost to the Saracens in 907, and throughout Leo's reign Byzantine seaports were raided by Muslim pirates. He modernized Justinian's laws.