Hydatius, also spelled Idacius (400-469) was a late Western Roman writer and clergyman. The bishop of Aquae Flaviae in the Roman province of Gallaecia (almost certainly the modern Chaves, Portugal, in the modern district of Vila Real), he was the author of a chronicle of his own times that provides us with our best evidence for the history of Hispania in the 5th century. Hydatius was born around the year 400 in the environs of Civitas Lemica, a Roman town near modern Xinzo de Limia in the Spanish Galician province of Ourense. As a young boy, he travelled as a pilgrim to the Holy Land with his mother, where he met Jerome in his hermitage at Bethlehem. About the year 417 he joined the clergy, and in 427 was consecrated bishop probably of Chaves (the Roman Aquae Flaviae) in Gallaecia. As bishop he had to come to terms with the presence of non-Roman powers, especially a succession of kings of the Suevi, in a province where imperial control became increasingly nominal during the course of his lifetime. The Suevi had settled in Gallaecia in 411, and there was constant friction between them and the local Hispano-Roman provincials. In this context, Hydatius took part in a deputation of the year 431 requesting assistance in dealing with the Suevi from the general Flavius Aëtius, the most important representative of the imperial government in the West. Along with this concern, Hydatius devoted himself to rooting out heresy, not just in his own episcopal diocese, but in the rest of Hispania as well. He was in frequent contact with some important bishops of the day, including Thoribius of Astorga and Antoninus of Mérida. Together with Thoribius, he petitioned Pope Leo I for assistance and advice in dealing with heresy. Though Hydatius consistently characterizes Hispanian heretics as Manichees, it is generally believed that he meant Priscillianists, followers of the ascetic bishop Priscillian, who had been condemned as a heretic by several church councils and executed as a magician by the emperor Magnus Maximus around 385.