Abstract
The third century CE was a period of turmoil for the Roman Empire, as can be seen for example in the disastrous years between 260-275 CE. The emperor Valerian had been captured by the Sasanids, and Rome was left scrambling to restore control. This allowed the Gallic Empire in the West and the Palmyrene Empire in the East the freedom to assert their dominance and independence from Rome. The resultant need for increased military expenditure during these years necessitated an increase in coin, which led to a massive and continuous debasement of the imperial antoninianus. Yet, despite the unequal demand for coin from the various imperial branch mints and the general chaos of the period, the imperial government maintained a surprisingly firm grasp on certain aspects of the economy.
This study argues that there was a policy of uniform debasement in the antoninianus – Rome’s standard silver coin in the third century – across the imperial branch mints between 260-275 CE, despite the apparent political and military chaos of the period. This will be achieved through comparing the weight and silver content of the antoninianus, analysed by King and Northover, from the imperial mints at Cyzicus, Mediolanum, and Rome. A similar approach was attempted by Philip Tyler, who concluded that there were unequal rates of debasement across the Empire. Tyler argued that during the sole reign of Gallienus, the imperial mint at Rome minted at two standards. Based on this assumption, Tyler suggested that the antoniniani of better quality were sent by the Rome mint to the East and the more debased antoniniani were sent to the West. Tyler reasoned that this was due to the differing military demands (and consequent financial demands) across the Empire. Tyler’s conclusions were not widely accepted by those prominent in the numismatic field. This study argues against Tyler’s findings through the use of more recent and more accurate analyses.