200 000 000 000 Mark

Speyer's two-hundred-billion Mark note is a product of the German hyperinflation at its most extreme — by late 1923, the Reichsbank could not supply sufficient currency fast enough, so municipalities, private firms, and regional bodies were authorized to issue their own emergency money, collectively known as Notgeld. Speyer's city administration was among hundreds of local issuers scrambling to meet payroll and basic commerce in denominations that would have been unimaginable two years earlier.

The inclusion of a watermark at this denomination level reflects a bureaucratic instinct toward security that the economic reality had already rendered absurd — a note worth two hundred billion Marks was, within weeks of printing, worth less than the paper it was struck on. The Rentenmark reform of November 1923 rendered the entire series void.