On March 31, 1854, the or was the first treaty between the
United States of America, and the
Empire of Japan, then under the administration of the
Tokugawa Shogunate. Signed under threat of force, it effectively meant the end of Japan’s 220-year-old policy of national seclusion (
sakoku), by opening the ports of
Shimoda and
Hakodate to American vessels. It also ensured the safety of American castaways and established the position of an American
consul in Japan. The treaty also precipitated the signing of similar treaties establishing diplomatic relations with other western powers.