The Women's suffrage in the United States of America, the legal right of women to vote, was established over the course of several decades, first in various states and localities, sometimes on a limited basis, and then nationally in 1920.
The demand for women's suffrage began to gather strength in the 1840s, emerging from the broader movement for women's rights. In 1848, the Seneca Falls Convention, the first women's rights convention, passed a resolution in favor of women's suffrage despite opposition from some of its organizers, who believed the idea was too extreme. By the time of the first National Women's Rights Convention in 1850, however, suffrage was becoming an increasingly important aspect of the movement's activities.
The first national suffrage organizations were established in 1869 when two competing organizations were formed, one led by Susan B. Anthony and Elizabeth Cady Stanton and the other by Lucy Stone. After years of rivalry, they merged in 1890 as the National American Woman Suffrage Association (NAWSA) with Anthony as its leading force.
Hoping the U.S. Supreme Court would rule that women had a constitutional right to vote, suffragists made several attempts to vote in the early 1870s and then filed lawsuits when they were turned away. Anthony actually succeeded in voting in 1872 but was arrested for that act and found guilty in a widely publicized trial that gave the movement fresh momentum. After the Supreme Court ruled against them in 1875, suffragists began the decades-long campaign for an amendment to the U.S. Constitution that would enfranchise women. Much of the movement's energy, however, went toward working for suffrage on a state-by-state basis.