Constantius II (b. Dalmatia (now in Croatia) - d. 2 Sep 421, Ravenna (Italy)), Roman emperor in 421.
Constantius came from Naissus (modern Nis, Yugoslavia) in the province of Moesia. In 411, as magister militium ("master of the soldiers") under the western Roman emperor Flavius Honorius (reigned 393-423), Constantius helped to overthrow the usurping emperor Constantine (Flavius Claudius Constantinus) at Arelate (modern Arles, France). He drove the Visigoths from southern Gaul into Spain in 415 but later recalled the tribe and settled it in southwestern Gaul. In 417 he married the emperor's half sister Galla Placidia. Appointed co-emperor of the West by Honorius, with the title augustus, on 8 Feb 421, Constantius died without having been recognized by the eastern emperor, Theodosius II. Constantius' son by Placida ruled the West as the emperor Valentinian III from 425 to 455.
[Encyclopaedia Britannica, 1995]