Gallienus in Wikipedia

Publius Licinius Egnatius Gallienus[1] (c. 218 – 268), commonly known as Gallienus, was Roman Emperor with his father Valerian from 253 to 260, and alone 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. Life - Rise to power Based on the testimony of John Malalas and the Epitome de Caesaribus that Gallienus was about 50 years old at the time of his death, it is generally considered he was born around 218, son of Valerian and Mariniana, a woman possibly of senatorial rank and possibly a daughter of Egnatius Victor Marinianus, and brother of Valerianus Minor.[2] Inscriptions on coins connect him with Falerii in Etruria and this may well have been his birthplace; it has yielded many inscriptions relating to his mother's family, the Egnatii.[3] He married to Cornelia Salonina about ten years before his accession to the throne. She was the mother of three princes, Valerian II (who died in 258), Saloninus (who, after becoming co-emperor, died in 260 by the hand of his general Postumus), and Marinianus[4] (killed in 268, shortly after his father was assassinated). When his father Valerian was proclaimed emperor on 22 October 253, he asked the Senate to ratify Gallienus' elevation to Caesar and Augustus, in order to share the power between two persons. He was also designated Consul Ordinarius for 254. As Marcus Aurelius and his adopted brother Lucius Verus had done a hundred years before them, Gallienus and his father divided the Empire; Valerian struck for the East to stem the Persian threat and Gallienus remained in Italy to repel the Germanic tribes on the Rhine and Danube. This policy made sense not simply because the unhappy fates of several Emperors previous to this duo had made it clear that one man simply could not rule a state this size; equally, a 'barbarian' enemy suing for peace in this time tended to demand that they be allowed to apply to the 'chief' or 'king' of the victorious side. Therefore, an Emperor had to be available to negotiate if such a situation arose...