1 000 000 000 Mark Bayerische Notenbank

The Bayerische Notenbank was one of four surviving German state banks still legally authorized to issue currency under the Reichsbank Law of 1875, a status that became acutely relevant in 1923 when the Reichsbank's own output could not keep pace with hyperinflation's demands. This billion-Mark note — a denomination unimaginable eighteen months earlier — was printed in Munich as a practical response to a collapse already beyond rational measurement. By November 1923, it would be worth a fraction of a US cent.

The watermark panel is the sole security feature, a telling indication of how quickly anti-counterfeiting considerations had become irrelevant when forgery could not keep up with official devaluation.