The Nineteenth Amendment
Ratified in August 1920, the Nineteenth Amendment forbids the federal government and the states from denying or abridging the right to vote on account of sex. It guaranteed women the right to vote throughout the United States.
The campaign for women's suffrage began at the Seneca Falls Convention in 1848 and ran for more than seventy years. Its leaders included Elizabeth Cady Stanton, Susan B. Anthony, Lucy Stone, Carrie Chapman Catt, and Alice Paul. They pursued multiple strategies in parallel. State-by-state campaigns won the franchise in Wyoming Territory in 1869 and in a growing list of Western states thereafter. By 1919, women could vote in fifteen states. Federal litigation and lobbying for a constitutional amendment proceeded alongside the state work. Paul and the National Woman's Party adopted militant tactics, including picketing the White House and accepting arrest and imprisonment.
The Nineteenth Amendment was first proposed in Congress in 1878 and reintroduced every year for decades without passage. The political environment shifted during World War I, as women's contributions to wartime industry and civic life made continued disenfranchisement increasingly indefensible. President Wilson, initially cool to the cause, came to support it. The House passed the amendment in May 1919, the Senate in June, and the required three-fourths of state legislatures ratified it by August 1920. The deciding vote came from Tennessee, where a young legislator named Harry Burn changed his position at the urging of his mother, breaking a tie in the state house.
The text is short: "The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of sex." Section 2 gives Congress the power to enforce the amendment by appropriate legislation. The effect was immediate in form and gradual in fact. Women voted in the 1920 presidential election in every state. Turnout among women rose steadily over the following decades and now consistently exceeds turnout among men. The amendment did not, on its own, guarantee equal political power. The path to that goal continued through the Civil Rights Act of 1964, Title IX of the Education Amendments of 1972, and a long series of Equal Protection decisions. The Nineteenth Amendment was the constitutional foundation on which all of that was built.