Mabel Vernon was an American suffragist, pacifist, and a national leader in the United States suffrage movement. She was a Quaker and a member of the National American Woman Suffrage Association. Vernon was inspired by the methods used by the Women's Social and Political Union in Britain. Vernon was one of the principal members of the Congressional Union for Women Suffrage (CUWS) alongside Olympia Brown, Inez Milholland, Crystal Eastman, Lucy Burns, and Alice Paul, and helped to organize the Silent Sentinels protests that involved daily picketing of Woodrow Wilson's White House.

The National Woman's Party (NWP) was an American women's political organization formed in 1916 to fight for women's suffrage. After achieving this goal with the 1920 adoption of the Nineteenth Amendment to the United States Constitution, the NWP advocated for other issues including the Equal Rights Amendment. The most prominent leader of the National Woman's Party was Alice Paul, and its most notable event was the 1917–1919 Silent Sentinels vigil outside the gates of the White House.