Roman emperor 253-268. His reign was a continual struggle against invasions and uprisings; at his death the empire was in a state of economic ruin and virtual anarchy. However, he was tolerant of Christianity and fond of the arts.

Publius Licinius Egnatius Gallienus (218-268) ruled the Roman Empire as co-emperor with his father Valerian from 253 to 260, and then as the sole Roman Emperor from 260 to 268. He took control of the empire at a time when it was undergoing great crisis. His record in dealing with those crises is mixed, as he won a number of military victories but was unable to keep much of his realm from seceding.