The history of counterfeiting is almost as extensive as the history of money itself.
It’s said that even the first electrum coins in Lydia were regularly faked, and coming across counterfeit coins in Ancient Rome was a daily occurrence. Roman Emperors, like other rulers, also famously did their own counterfeiting, debasing the metal in coins and trying to pass them off as having higher value.
The problem of funny money remained an issue for society even thousands of years later. For example, at the start of the U.S. Civil War in 1861 – when banks still issued their own currencies – it was estimated that half of the banknotes in circulation were forgeries.
Banknote Security Features
And as we move towards a more digital world, the cat and mouse games between authorities and counterfeiters continues.
Source: https://www.titlemax.com/discovery-center/money-finance/banknote-security-around-the-world/