"Constantius III (Flavius Constantius) was Roman emperor of the West in 421, from 8 February until his death on 2 September. He earned his position as Emperor due to his capability as a general under Honorius, achieving the rank of Magister militum by 411. That same year, he was sent to suppress the revolt of Constantine III, a Roman general who declared himself emperor. Constantius led his army to Arles in Gaul, the capital of Constantine III, and defeated Gerontius, a general rebelling against Constantine, before himself besieging Arles. After defeating a relief force led by Edobichus, Constantius convinced Constantine to surrender, promising safe retirement, but betrayed and beheaded him as soon as he surrendered. Constantius then went on to lead campaigns against various barbarian groups in Hispania and Gaul, recovering much of both for the Western Roman Empire. Constantius was proclaimed Western Roman Emperor by Honorius on 8 February 421. He reigned for seven months before dying on 2 September 421." - (en.wikipedia.org 11.08.2021)
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