5 000 000 000 Mark

Buer was a mid-sized industrial town in the Ruhr coalfield, and its municipal treasury — the Stadtkasse — was among the hundreds of local German authorities forced to print their own emergency currency in 1923 when Reichsbank supply collapsed entirely under hyperinflation. By the time denominations reached the billion-mark range, the practical problem was no longer monetary but logistical: notes had to be designed, approved, and physically produced faster than the currency lost value, often within days.

The five-billion-mark figure dates this note to late October or early November 1923, the absolute peak of the inflationary spiral before the Rentenmark stabilization of November 15th ended the crisis.