Flavius Valerius Severus Augustus
AD306 ~ AD307
Flavius Valerius Severus was originally a soldier from the Illyrian province until 305 when Galerius approached Maximian and requested he appoint Severus as Caesar of the western half of the roman empire. He was Caesar to Constantius who was Augustus of the western region at that time. When Constantius died a year later it was Galerius who promoted Severus to the position of Augustus, even though at the same time Constantine had been claimed emperor by his own soldiers.
Severus was sent to Rome with an army previously commanded by Maximian to repress the rebellion started when Maxentius (son of Maximian) revolted. Fearing the inevitable onslaught, Maxentius offered his retired father the opportunity to co-rule which Maximian accepted. Upon hearing this, the soldiers under Severus’ command rejected him and stood by their previous ruler.
Severus fled and when Maximian offered him safety he surrendered and was held captive near Rome in Tres Tabernae.
Galerius invaded Rome in 307 to suppress both Maximian and his son and at this time Maxentius had Severus murdered.