Source: Public Domain (Library of Congress)
The Nineteenth Amendment to the U.S. Constitution states:
“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.”
"The amendment was initially introduced in Congress in 1878. Finally approved by the necessary two-thirds majority in each house of Congress forty years later, it was sent to the states for ratification. In 1920 the amendment became a reality when Tennessee became the thirty-sixth state to ratify it. From the founding of the nation, it had taken more than a century for women to secure a constitutionally protected federal right to vote." In reality, it would be another 45 years before Black women were guaranteed voting rights.
Source: American Governance
The National Woman's Party (NWP) was formed in 1913 by Alice Paul and Lucy Burns after their Congressional Union for Woman Suffrage -- the committee they formed within the National American Woman Suffrage Association (NAWSA) to lobby Congress for a national women's suffrage amendment -- failed to gain any traction on Capitol Hill. Paul and Burns believed that the Union had been hampered by the fairly moderate stance of NAWSA, so they decided that more aggressive tactics were necessary in order to force the issue. Breaking with NAWSA allowed them to direct their efforts at a national audience, with greater freedom to employ acts of civil disobedience like boycotts and picket lines to draw attention to the cause of women's suffrage.
Indeed, the NWP was one of the first activist groups of the suffrage movement to use nonviolent resistance tactics, a strategy Burns and Paul had learned from English suffragist Emmeline Pankhurst. It was the combined efforts of Carrie Chapman Catt's state by state strategy and NWP's relentless direct action campaign that enabled final passage of the 19th Amendment in 1920. After the long campaign for suffrage, an exhausted Burns returned to private life, and Alice Paul shifted the NWP's focus to passage of the Equal Rights Amendment (ERA), which sought to eliminate gender-based discrimination. Drafted by Paul, it was introduced to Congress in 1923; the ERA was finally passed by Congress in 1972, but ratification efforts failed by three states. The NWP's efforts to bring about a constitutional guarantee of equal rights for women are ongoing.