Washington Naval Treaty Law and Legal Definition

The Washington Naval Treaty, limited the naval armaments of its five signatories: the United States of America, the British Empire, the Empire of Japan, the French Third Republic, and the Kingdom of Italy. The treaty was agreed at the Washington Naval Conference, which was held in Washington, D.C. from November 1921 to February 1922, and was signed by representatives of the treaty nations. It was an attempt to prevent a naval arms race that began after World War I.

The terms of the treaty were modified by the London Naval Treaty of 1930 and the Second London Naval Treaty of 1936. By the time of the latter, Japan had declared it would no longer abide by the terms of the treaty and Italy was secretly disregarding it. Germany was never affected by the Washington or London treaties; its naval construction was limited under the Treaty of Versailles, the peace treaty that ended World War I. Washington Naval Treaty is also known as the Five-Power Treaty.