What was the standard silver coin introduced by Charlemagne?

The standard silver coin introduced under Charlemagne was the denarius, also called the denier or penny in later languages.

Charlemagne’s monetary reforms built a silver-based system around the Carolingian pound. The accounting structure was 1 pound equal to 20 shillings, with each shilling equal to 12 denarii—240 silver pennies in total. The coin itself was the denomination normally struck and circulated; the pound and shilling were primarily units of weight or account.

The reform was developed in stages. Charlemagne’s father, Pepin the Short, had already strengthened royal control over minting and issued a new silver penny. Charlemagne later standardized the system, especially around 793–794, and required new denarii bearing his name or royal title. A typical coin also identified its mint, linking currency to royal authority.

The denarius can be confused with the Roman silver coin of the same name, but Charlemagne’s coin was a medieval successor rather than the ancient Roman issue. The solidus was mainly an accounting unit in this system, while the aureus and sestertius belonged to earlier Roman monetary traditions.