Finding Primary Sources

Primary sources are key to historians’ research. Due to age, composition, and exceptionality, primary sources are sometimes quite valuable and often require special attention. Repositories at the national, state, and local levels, as well as at the public and the private levels, preserve primary sources.

National repositories such as the National Archives and the Library of Congress safeguard materials that are deemed to be of national importance. Universities also have archives that preserve primary sources related to the institution, to notable alumni or donors, or to the research interests of their faculty. Museums and libraries at all levels have archives attached to their missions, and historical societies often preserve primary sources that are of local or niche interests to researchers.

Traditionally, historians visit such repositories and, with the assistance of archivists and finding guides, explore files of material pertinent to their research. The arrival of the Digital Age, however, resulted in many repositories scanning, digitizing, and posting their collections online. Online finding guides and search tools make looking for specific primary sources easier than it once was.

In order to make the most of finding primary sources online, you will need to be able to develop strong search terms to deploy in your search for primary sources. Generally, you will need to supply the name of the person or historical event you are researching. Usually, it is also helpful to identify a particular type of primary source document that you have in mind. Examples include:

• Letter
• Speech
• Interview
• Diary
• Oral history
• Journal
• Photograph

A historian who is researching primary sources on President Franklin Roosevelt’s interactions with American military leaders during World War II, for example, might start off by searching the Franklin D. Roosevelt Presidential Library and Museum’s online repository with the following search term: letter (Note: Since this is Roosevelt’s own library, the historian has chosen to omit Roosevelt’s name from the search).

A search like this will produce a lot of results, though. The historian in this example might add in the name of someone who he or she already knows is a major figure in the American military to narrow the search, such as Chief of Staff of the Army General Douglas MacArthur, the commander; the search then becomes letter Douglas MacArthur. This search produces a letter from Roosevelt to MacArthur that reveals some dynamics of their relationship.

While a wholly digital approach to research is not yet possible due to sheer volume and funding, the ability to both explore caches of digitized primary sources and to view online finding aids for non-digitized primary sources is a great boon to today’s historians.

1. Truman Library Collections
2. Voices of the Manhattan Project
3. National Security Archive

As you explore each repository, try to locate the following primary sources that you might consult to write a chapter about Szilard’s campaign against dropping the atomic bomb. Each primary source is located in only one of the above repositories. Try your best to locate each source, but it is OK if you are not able to locate all three. If you are successful in your search, try skimming through the sources you find.

1. The transcription of the oral history interview with Tom Evans, a close friend of President Truman’s, discussing scientists opposition to the use of the atomic bomb
2. A petition against the use of the atomic bomb circulated by Szilard directed toward President Truman
3. An interview with Lilli Hornig, a scientist who signed Szilard’s petition against the use of the atomic bomb

To do this, develop search terms similar to the examples shown in the overview. Only use these three online repositories to locate these sources—do not consult Google or any other search engine. Take notes on the search terms that are successful, and keep the links to the sources you find. You will need this for the short response activity in this learning block.