The Nineteenth Amendment prohibited denying Americans the vote because of sex.
Congress approved the amendment in June 1919, and Tennessee became the decisive 36th state to ratify it on August 18, 1920. Secretary of State Bainbridge Colby certified it on August 26, now observed in the United States as Women’s Equality Day.
The amendment resulted from a decades-long suffrage movement involving activists such as Susan B. Anthony, Elizabeth Cady Stanton, Ida B. Wells, and Carrie Chapman Catt. It built on earlier state-level voting reforms and the 1848 Seneca Falls Convention.
The amendment did not instantly give every woman equal access to the ballot. Racist state laws, intimidation, citizenship restrictions, and other barriers continued to disenfranchise many women of color, especially in the South, for years afterward.