Founded in 1919 by Herbert Hoover, the Hoover Library and Archives are among the world’s most important repositories for unique archival materials and rare publications on political, social, and economic change in the modern era.

While the Hoover Archives specializes primarily in unpublished materials (personal papers, sound recordings, posters, etc.), the Hoover Library is the Institution's repository for published books, serials, newspapers, and government documents. (Both the Library and Archives have pamphlets). The Library has particularly strong holdings on the Russian Revolution and the Soviet Union, Russian emigres, the world wars, the Paris Peace Conference, the League of Nations, and political and ideological movements of the 20th century.