Æ21 - Valerian and Gallienus C G I H P

Parion, the old Parian Greek colony on the Propontis, maintained active bronze coinage well into the third century under the Roman provincial system. This joint issue for Valerian and his son Gallienus places it within the co-regency period before Valerian's catastrophic capture by the Sasanian king Shapur I at the Battle of Edessa in 260 — an event that effectively ended Valerian's reign and left Gallienus to hold an empire fracturing on multiple frontiers simultaneously. Provincial mints like Parion ceased issuing bronze shortly after.