1911 Encyclopædia Britannica/Constantius, Flavius Valerius

CONSTANTIUS, FLAVIUS VALERIUS, commonly called Chlorus (the Pale), an epithet due to the Byzantine historians, Roman emperor and father of Constantine the Great, was born about A.D. 250. He was of Illyrian origin; a fictitious connexion with the family of Claudius Gothicus was attributed to him by Constantine. Having distinguished himself by his military ability and his able and gentle rule of Dalmatia, he was, on the 1st of March 293, adopted and appointed Caesar by Maximian, whose step-daughter, Flavia Maximiana Theodora, he had married in 289 after renouncing his wife Helena (the mother of Constantine). In the distribution of the provinces Gaul and Britain were allotted to Constantius. In Britain Carausius and subsequently Allectus had declared themselves independent, and it was not till 296 that, by the defeat of Allectus, it was re-united with the empire. In 298 Constantius overthrew the Alamanni in the territory of the Lingones (Langres) and strengthened the Rhine frontier. During the persecution of the Christians in 303 he behaved with great humanity. He obtained the title of Augustus on the 1st of May 305, and died the following year shortly before the 25th of July at Eboracum (York) during an expedition against the Picts and Scots.

See Aurelius Victor, De Caesaribus, 39; Eutropius ix. 14-23; Zosimus ii. 7.