Gerontius (magister militum)

Gerontius, probably a Briton by birth, was one of the supporters of Constantine III, a Roman general who revolted against the emperor Honorius in 407, conquering Britain, Gaul, Germania, and Hispania.

After losing his first battle against the rebels, Gerontius recalled additional forces from Gaul and won an important victory in Lusitania, where Didymus and Verenianus were captured.

Constans escorted the prisoners back to Gaul, while Gerontius remained in Hispania, in command of the local troops.

[3] In late spring 409, Gerontius rebelled against Constantine, who was now officially recognized as co-emperor by Honorius, and appointed Maximus as emperor.

[4] He moved to Tarraco, but left the city to oppose an invasion of Hispania by Constans, whom Constantine had newly appointed Augustus.