20 Gold Yen

Pick 37 belongs to the "Convertible Gilt Note" series, issued at a moment when Japan's gold standard commitments were already under strain. The First World War had disrupted international gold flows, and Japan suspended gold export in September 1917 — just two years after this note's issue date — effectively rendering the "convertible" promise hollow. Notes already in circulation continued to be used, but redemption in physical gold coin became impossible in practice.

The Cabinet Printing Bureau had been producing Bank of Japan notes since the Meiji period, giving the series a degree of technical consistency rare for the era. The watermark security on this denomination reflects the higher scrutiny applied to large-value notes in a country where counterfeiting concerns were taken seriously at the institutional level.