In 1853, a fleet of four U.S. battleships under the command of Commodore Matthew Perry sailed into what is now called Tokyo Bay.  This was in attempt to force Japan, which was closed to foreigners, to open the country.  When Commodore Perry returned to Japan again in 1854, the shogun, ruler of Japan at the time, concluded the U.S.-Japan Treaty of Amity.  As a result, the ports of Shimoda and Hakodate were opened to foreigners, and the shogun promised to supply such things as food, water and fuel to American ships.  This was how Japan's isolation from the rest of the world, which lasted for more than 200 years, came to an end.