Valerian

Valerian was proclaimed emperor by his troops after the death of Trebonianus Gallus. He appointed his son Gallienus as co-emperor, dividing the empire into eastern and western halves for administration. This arrangement aimed to address multiple external threats but ultimately failed to prevent Valerian's capture.

Valerian led a Roman army against the Sasanian Empire under Shapur I near Edessa. The Roman forces were defeated and Valerian was taken prisoner, becoming the first Roman emperor to be captured in battle. This event severely damaged Roman prestige and triggered a crisis of leadership.

Valerian died while a prisoner of the Sasanian king Shapur I. Accounts vary on the manner of his death, with some sources claiming he was used as a footstool by Shapur or flayed and his skin displayed. His death left the Roman Empire without a senior Augustus, worsening the Crisis of the Third Century.