Constans II - Augustus of Imperium Romanum from 409 AD to 411 AD
Constans II was the eldest son of the Western Roman Emperor Constantine III and was appointed co-emperor by him from 409 to 411.

Whether Constans II was a usurper is open to debate: he was crowned after Constantine III had been recognised as co-emperor by Honorius. However, this recognition would not have included the right to extend the imperial power to Constantine's family.

Constans was tasked with going to Hispania to fight barbarian invaders, but before leaving news came that Gerontius had stopped the invaders, had rebelled from Constantine, and had proclaimed Emperor one of his own men, Maximus of Hispania. With the support of the barbarians, Gerontius took over Constantine's territory, and in 411 he captured the city of Vienne and put Constans to death.
Constans II
Emperor Constans II of the Roman Empire