Subscriber: CNUA digital library of more than one million images in the arts, architecture, humanities, and social sciences. Other subject areas include music, religion, anthropology, literature, world history, American Studies, Asian Studies, Classical Studies, Medieval Studies, Renaissance Studies, and more.
"The Prints and Photographs Online Catalog (PPOC) contains catalog records and digital images representing a rich cross-section of still pictures held by the Prints & Photographs Division and, in some cases, other units of the Library of Congress. The Library of Congress offers broad public access to these materials as a contribution to education and scholarship.
The collections of the Prints & Photographs Division include photographs, fine and popular prints and drawings, posters, and architectural and engineering drawings. While international in scope, the collections are particularly rich in materials produced in, or documenting the history of, the United States and the lives, interests and achievements of the American people."
Suggested terms to look for include - diary, diaries, letters, papers, documents, documentary or correspondence.
Combine these these terms with the event or person you are researching. (example: civil war diary)
Also search by subject for specific people and events, then scan the titles for those keywords or others such as memoirs, autobiography, report, or personal narratives.