World War I Allies of World War I Central Powers Woodrow Wilson Paris Peace Conference League of Nations U.S. Senate Treaty of Versailles constitutional amendment women's suffrage Senate established President
The United States remained neutral from the outbreak of World War I in 1914 until 1917 when it joined the war as an "associated power" alongside the Allies of World War I, helping to turn the tide against the Central Powers. In 1919, President Woodrow Wilson took a leading diplomatic role at the Paris Peace Conference and advocated strongly for the U.S. to join the League of Nations. However, the U.S. Senate refused to support this and did not ratify the Treaty of Versailles under which the League of Nations was established.
In 1920, a constitutional amendment granted nationwide women's suffrage.
