The records of the American Jewish Historical Society, the oldest national ethnic historical organization in the United States, include correspondence of officers and staff as well as inter-office memos, multiple versions of the constitution and by-laws of the society, meeting minutes of administrative branches and committees, membership and financial records, reports, exhibit materials, records relating to the society’s library and archival holdings, press releases and newspaper clippings, and publications and newsletters created by the society. There are also materials from various programs, such as meetings and conferences, tours, lectures, awards and dinners, films, and educational programs.

The Annual and Mid-Winter National Conventions Records document the proceedings and outcomes of the conventions and conferences attended by Hadassah’s National Board as well as by convention delegates from the various regions of Hadassah. The conventions in particular are where local and regional leaders meet with each other and the National Board and learn about Hadassah’s various projects and committees. This record group also includes annual reports from 1926-2001.

Hadassah Functions and Operations Records represent the bulk of aid and services provided to Hadassah's membership, from the 1920s to 2011. Materials found in the record group include correspondence, clippings, press releases, manuals and kits for chapters and members to implement programming and chapter structure, fundraising campaigns, scripts, study guides, programming for local and national meetings, biographical files, and training documentation. Departments documented in the record group include Public Affairs, Education, Women's Health, American Affairs, Zionist and International Affairs, Speakers Bureau, Fundraising, Program, Organization, Outreach and Tourism Departments. Materials related to the general administration of Hadassah are also in the record group; these materials include research and development of projects, archives department correspondence and other materials, Hadassah House administration, and strategic planning. The record group also documents Hadassah's efforts to expand membership outside of the United States, by the development of Hadassah International.

The records of the People's Relief Committee for Jewish War Sufferers consist of correspondence with Jewish communities and relief organizations in Europe, Palestine, Cuba, South America, the United States, and Canada; as well as scrapbooks containing U.S. and Canadian Yiddish and English newspaper clippings and printed promotional literature pertaining to the fundraising activities of the People's Relief Committee in North America and abroad.

Jacques Judah Lyons, hazzan, rabbi and community leader, was born in Surinam and emigrated to Philadelphia in the early 1800s. Minister of the New York Congregation Shearith Israel for 38 years, he gathered extensive materials on early Jewish history in the United States, Canada and the West Indies. His papers include manuscripts, newspaper clippings, scrapbooks, notebooks, photographs, and a Sansom ship's log book. Contains material relating to Jews in North and South America generally and more specifically to Congregation Shearith Israel and the Jews in New York, the Touro Synagogue and cemetery and the Jews in Newport, Rhode Island, Philadelphia and the West Indies. Also contains material relating to Jews in the wars of the United States, correspondence of the Jews with George Washington and items relating to Haym Salomon. Collection consists of manuscript material and five notebooks and three scrapbooks of Lyons. Contains material not listed in calendar consisting of sermons by Lyons, a manuscript prayer book used in Surinam and a guide for religious ceremonies at Congregation Shearith Israel, as well as letters written during the Civil War period and correspondence relating to the personal life and career of Lyons.

The records chronicle the ideology behind the Reconstructionist movement, the founding and activities of the Jewish Reconstructionist Foundation, and its growth and transformation from an ideology and movement into an established American Jewish denomination, Reconstructionist Judaism. The records also document two seminal figures in Reconstructionist Judaism, Mordecai Menahem Kaplan and Ira Eisenstein. Included in the collection are the administrative records of the Foundation (minutes, financial records, bylaws), publications produced by the Foundation including manuscript submissions for the influential publication The Reconstructionist, correspondence, sermons, prayer books produced by the Foundation, syllabi, sheet music, photographs, and speeches, among other material. In the correspondence are letters from Martin Buber, J. Edgar Hoover, and Albert Schweitzer.

The children and descendants of Isaac Mendes and Rachel Levy Seixas included individuals who had a great impact on communal affairs and colonial Jewish life in New York, Philadelphia, Newport, and Richmond. Though this collection does not preserve the total volume of papers produced by every family member, the documents contained herein demonstrate the importance of the family in both Jewish and secular life in late 17th and early 18th century North America.

The collection is valuable to researchers studying the Seixas family; civic, mercantile, and religious contributions of Jews in the colonial era; Jewish communities in New York, Philadelphia, Newport, and Richmond; the importance of religion to Colonial Jews; Jewish participation in the Revolutionary War, the War of 1812, and World War I; Jewish converts to Christianity; Jews as masons; and Congregation Shearith Israel of New York.

Prominent individuals in this collection include: Ephraim Hart, Grace Seixas Judah, Mrs. Jesse Judah, Israel Baer Kursheedt, Sarah Seixas Kursheedt, Hayman Levy, Nicholas Low, Isaac Moses, Naphtali Taylor Phillips, Benjamin Mendes Seixas, David G. Seixas, Gershom Mendes Seixas, Isaac Benjamin Seixas, Isaac M. Seixas, Jacob B. Seixas, Joshua Seixas, and Moses Mendes Seixas.

The collection includes: account records, books, circumcision instructions and register, correspondence, drawings, estate papers, a eulogy, family trees, legal documents, petitions, photographs, prayer books, a sermon, and shipping records.

This collection is arranged into four series: Series I: Family Papers; Series II: Moses Seixas (1744-1809); Series III: Gershom Mendes Seixas (1746-1816) and descendants; and Series IV: Benjamin Mendes Seixas (1748-1817) and descendants.

Collection documents the activities and missions of the Union of Orthodox Jewish Congregations of America (UOJCA), primarily during the presidencies of William Weiss (1933-1942), Samuel Nirenstein (1942-1948), Moses Feuerstein (1954-1965), and Rabbi Pinchas Stolper’s tenure as Executive Vice President (1976-1994).

Founded in 1898, the UOJCA, also known as the Orthodox Union, serves as the leader, organizer, and voice of affiliated Orthodox Jewish congregations in North America. Divisions of the UOJCA reflected most prominently in the collection include the National Conference of Synagogue Youth, the Women’s Branch, the Kashruth Division, the Department of Synagogue Services, the Israel Center, as well as regional branches.

Subjects addressed in the collection include Sabbath and high holiday observance, dietary laws, Baal Teshuva, slaughterhouse legislation, funeral standards, education, and synagogue management and outreach. Materials include correspondence, minutes, clippings, speeches, UOJCA publications, financial documents, and a few photographs.