Valens, an emperor of the Roman Empire in the East. He came to power in 364 when his brother, Valentinian I, made him his associate. Both parts of the empire were threatened by Germanic peoples who were being forced westward by the Huns. Valens held his boundary at the Danube River, but in 376 he consented to let the Visigoths cross the river and settle in the empire. However, his generals so oppressed the Visigoths that they rose in rebellion. In 378 Valens met them in battle at Adrianople, where he was killed and the Eastern Roman army destroyed.