500 000 ECU

The ECU — European Currency Unit — was never a physical currency. It existed only as a basket-weighted accounting unit used in EC financial settlements, bond markets, and intergovernmental transactions from 1979 until it was superseded by the euro in 1999. No central bank ever issued ECU banknotes for circulation.

What exists under this description is almost certainly a privately produced novelty or souvenir item, likely printed in the 1980s or early 1990s during the peak of pro-European federalist enthusiasm. Several companies produced these, particularly in Belgium and France, with no official sanction and no monetary value. The 500,000 denomination is a clear tell — no serious monetary authority issues notes in that face value for a unit that never traded at retail level.

Not a banknote in any meaningful numismatic sense.