Æ25 - Valerian and Gallienus PROVINCIA DACIA, AN X

Provincia Dacia was a consolidated administrative fiction — three separate Dacian provinces (Dacia Apulensis, Dacia Malvensis, Dacia Porolissensis) grouped under a single governor from the mid-second century onward, and their provincial coinage reflected that political construct. The joint portrait of Valerian and Gallienus dates this piece to the narrow window of their co-rule before the catastrophe of 260, when Valerian was captured by Shapur I at Edessa — the only Roman emperor ever taken alive by a foreign enemy. AN X marks the tenth year of the Dacian provincial era, itself counted from 246 under Philip I.