Valerian (Licinius Valerianus) was consul under Severus Alexander (222-235 CE) and served as Roman emperor from 253 – 260 CE after he supported a rebellion against Maximinus in 238 CE. As emperor he established his son Gallienus as co-emperor of the west and rarely set foot in Rome as a result. (This model of co-emperorship was followed by Diocletian, who later established the tetrarchy.) Valerian also persecuted Christians and fought against the Goths and the Persians. After attempting to negotiate personally with the Persian king, Shapur I, Valerian died in Persian captivity.
Encyclopedia Britannica. 2020. “Valerian.” Encyclopedia Britannica. Accessed December 4, 2020. https://www.britannica.com/biography/Valerian-Roman-emperor.
Wasson, Donald L. 2017. “Valerian.” Ancient History Encyclopedia. Accessed December 1, 2020. https://www.ancient.eu/valerian/.