The Gallic Empire (Latin: Imperium Galliarum) was a breakaway realm of the Roman Empire led by Postumus (260-268AD) that existed from 260 to 274AD in the aftermath of the Persian capture of the Roman Emperor Valerian I (253-260AD) in 260AD. That set off a Financial Crisis in 260AD, where some even questioned if Roman coins were still valid. This Monetary Crisis of the Third Century AD saw the separation of the Roman Empire into three empires.
The Gallic Empire split from Rome and incorporated Britain, France, and parts of Spain. Postumus founded it in 260 AD. Valerian I was captured for once, and Germanic barbarians also began to invade, assuming that Rome was then vulnerable. The crisis led to people hoarding their money, and a great recession unfolded. The coinage began to be debased as silver was in short supply. This was the start of the collapse of Rome’s monetary system.
At its height, the Gallic Empire included the territories of even parts of Germania (Germany) along with Gaul (France), Britannia (England), and (briefly) Hispania (Spain). Postumus was assassinated in 268 AD, resulting in the Gallic Empire losing much of its territory. Roman Emperor Aurelian retook it after the Battle of Châlons in 274 AD.
Pair of Postumus Antoniniani = $375