What was the goal of the Fillmore Letter and How did Japan respond?

The Fillmore Letter, sent by President Millard Fillmore in 1853, aimed to open diplomatic and trade relations between the United States and Japan, which had been largely isolated from foreign influence. The letter requested that Japan allow American ships to refuel and trade at its ports. Japan initially responded with caution and reluctance, maintaining its isolationist policies for a time, but ultimately agreed to engage in negotiations, leading to the Treaty of Kanagawa in 1854, which opened Japanese ports to American ships.