Valentinian III(redirected from Flavius Placidius Valentinianus)
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Valentinian IIIad 419-455.
Emperor of Rome in the West (425-455) whose reign was marked by numerous raids by Germanic tribes.
(Biography) ?419–455 ad, emperor of the Western Roman Empire (425–455). His government lost Africa to the Vandals. With Pope Leo I he issued (444) an edict giving the bishop of Rome supremacy over the provincial churches