Æ24 - Valerian and Gallienus ΝΙΚΑΙΕΩΝ, ΔΙΟΝΥϹΙΑ, ΟΥΑΛΕ ΓΑΛ

Nicaea was one of the most prolific civic mints in Bithynia, continuing to strike bronze into the joint reign of Valerian I and Gallienus even as the Roman world fractured under the pressure of simultaneous frontier crises. The Διονύσια inscription references the festival games held in honor of Dionysus — a longstanding civic tradition that provincial cities used to assert cultural identity and attract imperial patronage. Nicaea's appeal to such festivals on coinage was partly political currency: demonstrating loyalty while advertising local prestige to Rome.

Valerian was captured by Shapur I of Persia around 260 AD, ending the joint reign abruptly.