Bonosus was a Roman usurper. Born in Hispania, his father was from Britain and his mother from Gaul. He lost his Brythonic father, a rhetorician and a "teacher of letters", early in life but his mother gave him a decent education. He had a distinguished military career, rising successively through the ranks and tribuneships, and an excellent service record when, stationed on the Rhine, the Germans managed to burn and destroy the fleet under his command.
Fearful of the consequence he proclaimed himself Roman emperor (ca. 281) at Cologne (Colonia Agrippina) jointly with Proculus. However, it did not save him from Probus, who after a lengthy and protracted struggle, managed to defeat him. Bonosus saw no way out and hanged himself.
He left behind a wife and two sons who were treated with honour by Probus.