Æ23 - Gordian III P M S COL VIM, AN II

Viminacium, a legionary fortress at the confluence of the Mlava and Danube rivers, became a Roman colony under Gordian III — likely in 239 AD — and immediately began issuing its own bronze coinage. Uniquely among provincial mints, Viminacium dated its coins by a local civic era beginning from that colonial grant, making AN II a precise chronological anchor rather than a regnal approximation.

The Moesian legions had played a decisive role in elevating Gordian III after the murders of Pupienus and Balbinus in 238. The colonial privilege extended to Viminacium may reflect that political debt.