Through the efforts of Alice Stone Blackwell, Harriot Stanton Blatch, and others, the National American Woman Suffrage Association (NAWSA) came into existence in 1890 and exerted an immediate impact on the movement, leading to suffrage victories in Wyoming, Colorado, Idaho, and Utah in the 1890s. Although most of the material in the NAWSA records (26,700 items; 1839-1961) dates from 1890 to 1930, the collection includes some information on the movement's early pioneers, including Susan B. Anthony, Elizabeth Cady Stanton, Sarah M. Grimké, Julia Ward Howe, Mary A. Livermore, Lucretia Mott, and Emma Willard. More recent leaders include Ida Husted Harper, Mary Garrett Hay, Belle Case La Follette, Maud Wood Park, Mary Gray Peck, Rosika Schwimmer, and Anna Howard Shaw. Of particular note in the records are progress reports from affiliated state and local suffrage organizations, papers relating to the work of the Congressional Union (which later became the National Woman's Party), literature on antisuffrage groups, information about international suffrage leaders and alliances, and files relating to suffrage songs and plays. (The Rare Book and Special Collections Division holds the NAWSA's Library.)

Included among the NAWSA manuscript materials are items relating to the Leslie Woman Suffrage Commission, which was established by NAWSA president Carrie Chapman Catt (1859-1947) with a one-million-dollar bequest she inherited in 1914 from newspaper publisher Miriam Florence Leslie. Catt appointed journalist Ida Husted Harper to the commission's newly created Leslie Bureau of Suffrage Education, with the job of generating press releases and reports in favor of the federal suffrage amendment and responding to editorials critical of women's suffrage and of the tactics used by the NAWSA's militant offshoot organization, the National Woman's Party. In addition to the NAWSA materials, Harper's work is documented in a separate Manuscript Division collection of Leslie Woman Suffrage Commission Records (1,200 items; 1911-18).

The records of the National Woman's Party (343,400 items, 275 microfilm reels, 101, 529 digital files (459.60 GB);1850-2022) trace the development of that organization from its beginnings in late 1912 when Alice Paul and Lucy Burns, young Americans who had worked with Emmeline and Christabel Pankhurst in the British suffrage movement, sought appointments on the lethargic NAWSA Congressional Committee so that they could work toward passage of a federal suffrage amendment. Their first activity was to organize the massive March 3, 1913, national suffrage parade (see “Marching for the Vote”), which was followed by other efforts to increase pressure on Congress and President Woodrow Wilson. Finding themselves at odds with the NAWSA leadership, Paul and Burns left the Congressional Committee in late 1913 to form the Congressional Union, a NAWSA affiliate that became independent of the parent body in February 1914 and was later reorganized as the National Woman's Party (NWP) in June 1916.

The NWP records held by the Manuscript Division are divided into four major groups:

• Group I, dating mainly 1912-20, covers all aspects of the party's suffrage campaign, including its use of pickets, parades, demonstrations, arrests, hunger strikes, and other “militant” tactics. Hundreds of photographs of individuals, groups, and events are found here, in addition to voluminous files of correspondence, minutes of meetings, reports, financial and legal records, and printed matter. Approximately 450 photographs from Group I and Group II have been digitized as part of Women of Protest: Photographs from the Records of the National Woman's Party on the Library of Congress Digital Collections site. The Microfilming Corporation of America produced a microfilm edition of the Group I materials in 1981, and researchers are required to consult the microfilm edition first. Researchers may view a copy of the microfilm edition in the Manuscript Reading Room, or they may request selected reels on interlibrary loan through an academic or public library in their community. In addition to the finding aid prepared by the Manuscript Division, there exists a detailed description of the Group I materials in a printed guide, National Woman's Party Papers: The Suffrage Years, 1913-1920, edited by Donald L. Haggerty and published by the Microfilming Corporation of America.
• Groups II and III date from 1913 to 1974 and include some suffrage material but relate primarily to the organization's post-1920 initiatives, principally its efforts to gain passage of a federal Equal Rights Amendment (ERA), drafted by Paul and first introduced in Congress in December 1923. The Microfilming Corporation of America organized and microfilmed the Group II materials in 1979 before the National Woman's Party donated them to the Library of Congress. Researchers are required to consult this microfilm edition first. The Group II materials, which are described in both a finding aid prepared by the Manuscript Division and a guide published by the Microfilming Corporation of America, titled National Woman's Party Papers, 1913-1974, edited by Thomas C. Pardo. The records in Group III consist principally of items not selected by the Microfilming Corporation of America for inclusion in its microfilm edition. These records were subsequently organized and described in a finding aid by the Manuscript Division.
• Group IV of the National Woman's Party Records is composed of three separate additions, which were organized and described by the Manuscript Division in 2003. Additions I and II are comprised of material, which for various reasons, had not been included in the arrangement and microfilming of Groups I and II, respectively. Many of the items in Addition I duplicate material from the microfilm edition of Group I, but both sources should be consulted to obtain a more complete record of the organization's suffrage campaign. Addition II contains mostly material not duplicated on the microfilm of Group II and includes the personal papers of NWP officers and members Jean Kane Foulke, Lucia Hanna Hadley, Dora G. Ogle, Alice Paul, and Helen Hunt West. Addition III was acquired from an independent source and was never microfilmed. It contains correspondence, administrative files, subject files, and miscellaneous items relating to the organization's financing, legislative initiatives and strategies to promote the Equal Rights Amendment, and involvement with the International Woman Suffrage Alliance. The correspondence files of Alice Paul and Anita Pollitzer are of particular note.
• Group V of the National Woman's Party Records represents the final additions of material from the National Woman's Party as it prepared to dissolve the organization in 2020. The physical number of items in Group V is nearly the size of Groups I-IV combined, and also includes a significant digital component. The records of Group V span the entire existence of the National Woman's Party (NWP) and also include posters, photographs, and printed matter documenting the suffrage movement prior to NWP's founding. All material post-1975 is found in Group V.

In addition to its campaigns for women's suffrage and the ERA, the NWP also fought successfully for more favorable nationality laws and equal citizenship rights for women, including the Cable Act of 1922 and its subsequent revisions, the Dickstein-Copeland Bill of 1934 and the Equal Nationality Treaty of 1934. State laws also came under the NWP's review, and the organization's Legal Research Department prepared extensive reports on women's legal status in each state and drafted bills for state legislatures concerning parents' custody rights, jury service, property rights, reinstatement of maiden name after marriage, divorce rights, estate administration, and guardianship issues. The dissolution of the NWP in the early 1990s, following a contentious internal legal fight, may be traced in the records of the Woman's Party Corporation (11,480 items; 1918-98; bulk 1985-95) and in Group V of the NWP Records. A digital version of Group I and Group II of the National Woman's Party records is also available via the subscription database ProQuest History Vault.