Primary sources are the building blocks of historical research - they are the documents or artifacts closest to the topic of investigation that you will use as evidence to support your interpretation of the past. Often they are created during the time period which is being studied (e.g. correspondence, diaries, newspapers, government documents, art), but they can also be produced later by eyewitnesses or participants (memoirs, oral histories). You may find primary sources in their original format--often in an archive--or reproduced in a variety of ways: published in books, on microfilm, or digitized in a searchable database.
For comparison, secondary sources are narratives, interpretations, and critical analyses of the past, written by historians or others and (hopefully) based on primary sources. They are created by writers who have the necessary distance in time to put past events and people into their broader historical context. Secondary sources build upon and interpret primary sources, and typically respond to and debate with the secondary sources created by others. Secondary sources also come in a variety of formats, including peer-reviewed books and journal articles, presentations at conferences, professional blog posts, or magazine articles.
Primary sources are typically organized according to who created them.
When looking for primary sources, think about who would have documented the people, places, and events that interest you, keeping in mind that those documents might be written by participants, outside observers, or even opponents of your subject matter. This guide presents possible primary source materials first by source type, such as one person's papers (letters sent to colleagues, professional work, budgets), newspapers, or documents created by government agencies.
Our research projects might use a wide range of source types, but perhaps are limited to a particular place and time. Thus, this guide also offers further suggestions organized by geographic region.
With primary sources, the possibilities are endless.
This research guide is not a comprehensive list of primary source collections that might be relevant to your topic. Historians are constantly innovating in the way they use traditional sources and finding creative ways to work with new ones.
You are not alone. Ask an expert!
Research with primary sources is a collaborative effort. Experts in your field will know how resources have been used by other historians, and can help you to think creatively about what types of sources to use. Librarians and archivists are skilled at talking through your research project and connecting you to materials in their collections and beyond. And don't forget to consult the bibliographies and citations of other historians to get ideas on what sources to use (and where to find them).
We often associate primary sources with archives, and secondary sources with libraries, but you can find primary sources in both places. However, it's important to note that these institutions organize information and collections differently.
Locating primary sources for historical research is an iterative process. It often involves consulting the secondary sources, tracking down primary sources used and cited by others, and frequently returning to the literature as new names, events, and concepts emerge.
Search for authors - Individuals, organizations, and government branches/agencies can all be authors, and can be searched in library catalogs accordingly. Results might include autobiographies, published correspondence and diaries, interviews, government reports, hearings, and studies, periodicals and bulletins, and archival collections.
Search for formats - In a library catalog, published and unpublished primary source materials often have a subject heading that indicates its format. See the "On the Shelves, In the Catalog" box on this page for some suggestions.
Know your subject headings - It helps to get to know how subject headings are used to describe your topic. For example, the subject headings Cuban Americans and Cubans--United States have slightly different meanings, and both could be useful for studying Americans of Cuban origin or Cubans in the United States, respectively.