The diassarion was a bronze coin introduced during the Roman Empire as part of the complex monetary system of the provinces, particularly in the Greek-speaking eastern regions. Its name derives from Greek, meaning “two asses,” indicating its value as equivalent to two asses, a basic unit of Roman bronze currency. The diassarion is notable for its regional use and its role in the localized economies of the Empire.

The diassarion emerged during the late 1st century CE, a period when the Roman Empire allowed a degree of monetary autonomy to its provinces. While silver denarii and gold aurei served as the primary currencies for larger transactions across the Empire, local bronze coinage like the diassarion was minted to facilitate everyday commerce. These coins often featured imagery tailored to the specific cities or provinces where they were produced, including depictions of local gods, important landmarks, or civic symbols.

The circulation of diassaria declined by the mid-3rd century CE as the Roman monetary system underwent significant changes. The increasing debasement of silver coins like the denarius and the introduction of new coinage, such as the antoninianus, disrupted the established currency system. Additionally, the economic and administrative challenges of the late Empire reduced the production of localized bronze coinage in favor of more standardized issues.