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.
Bust, Palatine Museum
Bust of Cornelia Salonina
A bas relief of Emperor Valerian standing at the background and held captive by Shapur I was found at Naqsh-e Rustam, Shiraz, Iran. The kneeling man is probably Philip the Arab.
Antoninianus of Postumus. Legend:IMP. C. POSTVMVS P. F. AVG.
The Roman emperor was the ruler and monarchical head of state of the Roman Empire, starting with the granting of the title augustus to Octavian in 27 BC. The term "emperor" is a modern convention, and did not exist as such during the Empire. Often when a given Roman is described as becoming emperor in English, it reflects his taking of the title augustus and later basileus. Another title used was imperator, originally a military honorific, and caesar, originally a surname. Early emperors also used the title princeps alongside other Republican titles, notably consul and pontifex maximus.
Bust of Augustus wearing the corona civica
Augustus depicted as a magistrate at the Ny Carlsberg Glyptotek
Cameo of Augustus in a quadriga drawn by tritons at the Kunsthistorisches Museum, Vienna
Denarius of Augustus (18 BC).