American-Japanese Treaty.
A treaty negotiated between the Shôgun and Commodore Perry on behalf of the United States in 1854, by which Japan opened the ports of Yokohama, Kobe, Nagasaki, and Hakodaté to foreign commerce. Foreigners had been excluded from Japan for 216 years before this date, with the exception of the Dutch, who however were strictly confined to their factory at Deshima.