Constantine III was a Roman general who was elevated as the emperor in Britain in 407. He crossed to the continent and there his armies, led by Iustinianus and Nebiogastes, and later by Edobichus and Gerontius, were fighting with Sarus, lieutenant of Stilicho, whom he eventually forced to retreat to Italy. In 408 Constantine established his capital in Arles, and after the next war he won with the Roman armies of Honorius he was recognised as co-emperor. Later however he had to deal with the revolt of his own general Gerontius. Gerontius defeated the forces of Constantine III's son Constans in Vienne in 411, and consequently besieged Constantine III in Arles. Constantius, a general of Honorius, defeated Gerontius and continued the siege of Arles. The remaining support of Constantine in Gaul abandoned him to support the rebel Jovinus. Constantine surrendered, and was ordained a presbyter, imprisoned, and finally killed (Blockley 2008: 129-130; Drinkwater 1998).
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