To get a sense of its content, search for UNITED STATES HISTORY. A more specific search can yield solid results (e.g., Roosevelt Corollary or USS JUNEAU). National parks can also be solid sources of information. Try: NATIONAL PARKS "CIVIL WAR"

Digital Collections tab leads to links that include American Culture & History (American Memory project), Chronicling American (historic American newspapers, 1860-1922).

Primary sources in American social history(antebellum period through reconstruction). Includes books, journals, link to Univ of Michigan digital collection.

Famous speeches in politics and movies as well as debates, interviews, and even classic skits.
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Information organized by modules (e.g., Jacksonian Era, Westward Expansion, Reconstruction).