Publius Licinius Egnatius Gallienus was a Roman Emperor who ruled from 253 to 268 AD. He was the son of Emperor Valerian and was proclaimed co-emperor alongside his father in 253. During his reign, Gallienus was successful in restoring
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Publius Licinius Egnatius Gallienus was Roman emperor with his father Valerian from 253 to 260 and alone from 260 to 268. He ruled during the Crisis of the Third Century that nearly caused the collapse of the empire. He won numerous military victories against usurpers and Germanic tribes, but was unable to prevent the secession of important provinces. His 15-year reign was the longest in half a century.