The Washington Naval Conference was held from 1921 to 1922 in Washington, D.C., aimed at addressing naval disarmament and preventing an arms race after World War I. Major world powers, including the United States, the United Kingdom, Japan, France, and Italy, participated in the conference to discuss limitations on naval construction and to promote peace. One of the key outcomes was the signing of the Five-Power Treaty, which established ratios for battleship tonnage among the participating nations. This agreement sought to reduce naval fleets and prevent future conflicts, marking a significant effort in international diplomacy during the interwar period.