1 Shu 'Ansei Isshugin'

The Ansei Isshugin was struck following the forced opening of Japanese ports under the Convention of Kanagawa in 1854, a direct response to Commodore Perry's expedition. Foreign merchants exploited the exchange rate between Japanese gold and silver — drastically out of alignment with global ratios — to drain the country of gold coins at enormous profit. The Shogunate's monetary reforms during this decade were partly an attempt to stem that hemorrhage, though they proved largely ineffective before the system collapsed entirely at the Meiji Restoration.