400 Cash Da-Ming Baochao

The Da-Ming Baochao series, introduced under the Hongwu Emperor in 1375, was backed by nothing except imperial decree — there was no silver or copper reserve, and no redemption mechanism was ever seriously implemented. The government also banned the use of copper cash and silver for private transactions in the same period, an attempt to force public adoption that generated widespread evasion rather than confidence.

Mulberry bark paper was specified precisely because it was difficult to source outside official channels, an early anti-counterfeiting measure that worked better in theory than in practice. Forgery was punishable by death, with rewards offered to informants — including the forger's own neighbors.

By the mid-fifteenth century the notes had lost most of their face value through chronic overissue, and the Ming government quietly stopped defending the currency altogether.