Justinian I, 483-565, Byzantine emperor (527-65), nephew and successor of Justin I. He was responsible for much imperial policy during his uncle's reign. Soon after becoming emperor, Justinian instituted major administrative changes and tried to increase state revenues at the expense of his subjects. Justinian's fiscal policies, the discontent of the Monophysites at his orthodoxy, and the loyalty of the populace to the family of Anastasius I produced the Nika riot (532), which would have cost Justinian his throne but for the firmness of his wife, Empress Theodora, and the aid of his great generals, Belisarius and Narses (see Blues and Greens). Justinian, through Belisarius and Narses, recovered Africa from the Vandals (533-48) and Italy from the Ostrogoths (535-54). He was less successful in fighting the Persians and was unable to prevent the raids of the Slavs and the Bulgars. Justinian's policy of caesaropapism (i.e., the supremacy of the emperor over the church) included not only matters of organization, but also matters of dogma. In 553, seeking to reconcile the Monophysites to the church, he called a council (see Constantinople, Second Council of) but accomplished nothing and finally tended to drift into heresy himself. Justinian's greatest accomplishment was the codification of Roman law, commonly called the Corpus Juris Civilis, executed under his direction by Tribonian. It gave unity to the centralized state and greatly influenced all subsequent legal history. Justinian erected many public works, of which the church of Hagia Sophia is the most notable. He was succeeded by his nephew, Justin II. The writings of Procopius are the main source of information on Justinian's reign.

orig. Petrus Sabbatius

(born 483, Tauresium, Dardania—died Nov. 14, 565, Constantinople) Byzantine emperor (527–565). Determined to regain former Roman provinces lost to barbarian invaders, Justinian conquered the Vandals in northern Africa in 534 and enjoyed an initial victory over the Ostrogoths in Italy in 540. War with the Goths, however, lasted another two decades and brought great devastation before Justinian gained control of the whole of Italy in 562 . He was unable to prevent Bulgars, Slavs, Huns, and Avars from carrying out raids along the empire's northern frontier. He also carried on an intermittent war with Persia until 561. He reorganized the imperial government and commissioned the reform and codification of the great body of Roman law known as the Code of Justinian. His efforts to root out corruption triggered a revolt in Constantinople in 532 that nearly toppled his government; his wife, Theodora, helped him put down the revolt. Like all Roman emperors, Justinian was an active builder, and his many public works projects included the reconstruction of cities and the construction of the church of Hagia Sophia, one of the finest and most famous buildings in the world.

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