ECU Carolus Magnus

The "Carolus Magnus" ECU was part of a wave of privately and semi-officially issued gold ECU pieces produced in the early 1990s, timed to coincide with the Maastricht Treaty ratification and the anticipated transition to a unified European currency. The ECU itself was never legal tender in the conventional sense — it existed as a basket currency unit used in European Community accounting and bond markets, which gave mints and issuers considerable latitude to produce commemorative pieces without central bank authorization.

Charlemagne's association with European unity was a deliberate political choice, his Frankish empire having been the last time much of the continent operated under a single administrative authority before the modern project.