The Treaty of Washington was a treaty signed and ratified by the United Kingdom and the United States in 1871 during the presidency of Ulysses S. Grant that settled various disputes between the countries, including the Alabama Claims, illegal fishing by American trawler men in Canadian waters and compensation for British civilian losses in the American Civil War. It had a significant effect on the United States' long-term relationship with Canada, and Britain, establishing international law between these countries.
In early 1871, the British government sent Sir John Rose to the United States to ascertain whether negotiations to settle the Northwestern boundary dispute would be acceptable to President Ulysses S. Grant. The U.S. government through the adroit and diplomatic abilities of Grant's Secretary of State, Hamilton Fish, cordially received his advances and, on January 26, Sir Edward Thornton, the British Minister at Washington formally proposed the appointment of a joint high commission to meet in Washington to resolve the dispute. The United States readily consented, provided that the differences growing out of the Civil War be among the subjects to be considered. The British government promptly accepted the American proviso and the president appointed commissioners.
The British government selected as its commissioners Earl de Grey (Marquess of Ripon), Sir Stafford Northcote, Lord Tenterden, Sir Edward Thornton, Mountague Bernard, and Canadian Prime Minister Sir John A. Macdonald. President Grant appointed U.S. commissioners Secretary of State Hamilton Fish, who served as chairman, Robert Schenck, Ebenezer R. Hoar, George Henry Williams, Samuel Nelson, J.C. Bancroft Davis.