Follis: The Evolution of Roman and Byzantine Bronze Coin

Illustrated Specimen Details: Follis

Example Specimen: Constantine I, 314-315 AD (Roman Empire)

The coin shown above is a bronze follis minted between 314 and 315 AD during the reign of Constantine I (Constantine the Great).

• Obverse: Features a laureate bust of Constantine I. The legend reads IMP CONSTANTINVS P F AVG (Imperator Constantinus Pius Felix Augustus — Emperor Constantine Pious and Blessed Augustus).
• Reverse: Depicts naked Sol, the personification of the Sun. The legend SOLI INVICTO COMITI translates to "To the Invincible Sun, companion of the Emperor." The letters R, F, X possibly stand for "Roma Felix." The mint mark RQ indicates the Rome mint, 4th officina.

1. ROMAN EMPIRE (3rd-4th centuries)
2. BYZANTINE EMPIRE (6th-12th centuries): 1 follis = 40 nummi
3. CRUSADER STATES (12th century): Principality of Antioch and County of Edessa
4. KINGDOM OF HUNGARY (12th century): "scyphate follis"
5. BULGARIAN EMPIRE (12th-13th centuries): "imitation of follis"

The name of the coin (follis) originally meant a "bag" or "purse" in Latin, likely referring to a sealed bag containing a fixed, counted sum of small change. Another compelling theory links it to the Greek word "φολίς" (thin layer), a direct reference to the thin wash of silver that coated the earliest issues of these bronze coins.

The Follis: History and Evolution in the Ancient World

The follis was a major bronze denomination that served as a recurring concept in late Roman and early Byzantine monetary history. Rather than remaining a single fixed coin, it was a large base-metal denomination repeatedly introduced, modified, and redefined in response to severe economic challenges and inflation.

The Roman Period and Diocletian's Reform (from 294 AD)

The follis was first introduced around 294-296 AD during the sweeping monetary reforms of Emperor Diocletian. This initiative aimed to stabilize an economy exhausted by a long period of inflation and currency debasement. Conceived as a large, standardized coin, the early follis was substantial, weighing between 8 and 10 grams. It contained a small amount of silver (about 4 percent) and was coated with a thin silver layer to give it a more valuable appearance and restore public confidence.

Despite this strong start, the follis quickly fell victim to the very inflation it was meant to combat. Throughout the 4th century, especially under the successors of Constantine the Great, the coin underwent progressive reductions. What began as a substantial, silvered piece constantly decreased in both weight and size, eventually losing its silver content entirely as it mirrored the broader economic pressures within the empire.

The Byzantine Period and Anastasius I (from 498 AD)

The follis found new life in the Byzantine period. In 498 AD, Emperor Anastasius I conducted a landmark reform that reintroduced the follis as a large, clearly defined copper coin. This reform established a transparent and standardized system of bronze denominations that became the cornerstone of daily commerce in urban markets.

The most recognizable feature of the Byzantine follis is the use of prominent Greek numerals on the reverse to indicate its value within a new fractional system:

• M — follis (valued at 40 nummi)
• K — half-follis (20 nummi)
• I — decanummium (10 nummi)
• E — pentanummium (5 nummi)

While the obverse typically depicted the emperor in facing or profile view holding the regalia of power, the reverse clearly indicated the value, the abbreviated mint name, and the regnal year. This practical and highly legible system allowed the follis to remain in active circulation for centuries, making it one of the most enduring and recognizable coin types of the Byzantine era.