The 19th Amendment (1920) to the Constitution of the United States provides men and women with equal voting rights. The amendment states that the right of citizens to vote "shall not be denied or abridged by the United States or by any State on account of sex." Although this equality was implied in the 14th Amendment (1868), most of the states continued to restrict or prohibit women's suffrage.

The women's rights movements, which started as early as the 1830s and became intertwined with the struggle to abolish slavery, resulted in the proposal for the 19th Amendment, introduced in Congress in 1878. This proposed amendment remained a controversial issue for over 40 years, during which the women's rights movement became strongly militant, conducting campaigns and demonstrations for congressional passage of the amendment and then for ratification by the states. This political action, reinforced by the service of women in industry during World War I, resulted in the adoption of the amendment.

Darcy, R. W., et al., Women, Elections, and Representation (1987; repr. 1994).
Kraditor, A. S., The Ideas of the Woman Suffrage Movement (1965; repr. 1981).
Langley, W. E. , and Fox, V. C., eds., Women's Rights in America (1994).
Rogers, D. W., ed., Voting and the Spirit of American Democracy: Essays on the History of Voting and Voting Rights in America (1992).