Antoninianus - Postumus P M TR P COS II P P

Postumus founded the Gallic Empire in 260 AD after executing Saloninus, the teenage co-emperor left in charge of the Rhine frontier by his father Gallienus. Rather than march on Rome, Postumus consolidated control over Gaul, Britannia, and Hispania, ruling for nearly a decade — an extraordinary tenure for a usurper in the crisis-ridden third century. His reluctance to push east almost certainly prolonged his reign.

The COS II dating places this piece in his second consulship, still early in that reign. Postumus held the consulship annually with himself as colleague, a pointed assertion of legitimacy. He was killed by his own troops in 269 after refusing to allow them to sack Mainz.