After coming to power in the early 17th century, the Tokugawa shogunate had kept Japan in a state of isolation ("sakoku") for a period of more than 250 years. This isolation was brought to an end in the 1850s by the arrival of American and British forces who demanded the opening of Japan's ports to trade. After initial resistance the Treaty of Amity and Commerce was signed between the United States in July 1858 and Hyogo Port was opened to American trade on 1 January 1860.