Theodosius I

Theodosius I, full name Flavius Theodosius, called Theodosius the Great (346?-395), Roman emperor of the East (379-395) and of the West (394-395), the last man to rule a united Roman Empire. Theodosius was born in Spain, the son of the Roman general Theodosius. As a young man he accompanied his father on campaigns in Britain, but on his father's death he retired to Spain. When the eastern Roman emperor Valens was killed fighting the Visigoths at Adrianople in 378, the western Roman emperor Gratian chose Theodosius to rule in the East; he was crowned the following year. In 382, after numerous skirmishes, Theodosius negotiated a favorable peace with the Goths, permitting them to reside in his empire on the condition that they serve in his army. After the murder of Gratian in 383, Theodosius recognized the usurper Magnus Clemens Maximus as emperor of the West, with the exception of Italy, where Valentinian II continued to rule as Gratian's legal successor. When Maximus invaded Italy in 388, Theodosius defeated and killed him and restored Valentinian as Roman emperor of the West.

Theodosius was a strong champion of orthodox Christianity; he persecuted the Arians and discouraged the practice of the old Roman pagan religion. In 390, however, he ordered the massacre of 7000 insurgent citizens of Thessaloníki, Greece, and was excommunicated by Bishop Ambrose of Milan, who demanded public penance before lifting the ban. In 392 Valentinian was murdered by his general Arbogast, who set up Eugenius as puppet ruler in his place. Theodosius again marched to Italy, where he defeated Arbogast and Eugenius in September 394. During the following four months he was the ruler of both East and West. After his death at Milan on January 17, 395, he was succeeded by his sons Arcadius in the East and Flavius Honorius in the West.