Understanding primary sources
If you are seeking to learn about the past, primary sources of information are those that provide first-hand accounts of the events, practices, or conditions you are researching. In general, these are documents that were created by the witnesses or first recorders of these events at about the time they occurred, and include diaries, letters, reports, photographs, creative works, financial records, memos, and newspaper articles (to name just a few types).
Also because primary sources are interdisciplinary it may be helpful to check out the Primary Source section of the History Subject Guide.
Primary sources also include first-hand accounts that were documented later, such as autobiographies, memoirs, and oral histories. However, the most useful primary sources are usually considered to be those that were created closest to the time period you’re researching.
Determining which kinds of documents constitute primary sources depends upon the topic you’re researching. (For example, sometimes the same book or article could be considered a primary source for one research topic and a secondary source for a different topic.)
For Example: The painting of Washington Crossing The Delaware, by Emanuel Leutze was painted in 1851.
This painting is both a primary and secondary source depending on what you are researching.
It is a primary source if you are studying the painter Emanuel Leutze or art and paintings from the late 19th century.
It is a secondary source if you are studying the American Revolution or the actual event of Washington crossing the Delaware, this is because the events depicted in the painting took place in 1776, over 50 years before the painting was painted. Emanuel Leutze was not present for the events he is depicting so it cannot be a primary source for those events.
Primary, Secondary, & Tertiary Sources
Primary sources of information are original materials that often convey new ideas, discoveries, or information. These sources originate from the time period under study. Examples of primary sources include:
- original research studies (often in the form of journal articles in peer-reviewed publications), also called empirical studies (e.g. psychology)
- patents, technical reports
- original documents such as diaries, letters, emails, manuscripts, lab data/notes
- newspaper articles from the time period under study
- autobiographies, first-person accounts, case studies
- artifacts and archival material such as official documents, minutes recorded by government agencies and organizations, photographs, coins, fossils, natural specimens
- works of art such as literature, music, architecture, or painting
Secondary sources of information are based on primary sources. They are generally written at a later date and provide some discussion, analysis, or interpretation of the original primary source. Examples of secondary sources include:
- review articles or analyses of research studies about the same topic (also often in peer-reviewed publications)
- biographies, reviews, or critiques of an author
- analyses of original documents or archival material
Tertiary sources of information are based on a collection of primary and secondary sources.
These are sources that index, abstract, organize, compile, or digest other sources. Some reference materials and textbooks are considered tertiary sources when their chief purpose is to list, summarize or simply repackage ideas or other information. Tertiary sources are usually not credited to a particular author.
- textbooks (sometimes considered as secondary sources)
- dictionaries and encyclopedias
- manuals, guidebooks, directories, almanacs
- indexes and bibliographies
TIP: What is considered primary, secondary, or tertiary information may vary according to your field of study. When in doubt, ask your professor.
For additional primary sources see the Primary Sources page on the English Subject Guide.
African American Newspapers: The 19th Century (Accessible Archives)
America's Historical Newspapers (Readex)
American Periodicals (ProQuest)
Black Historical Newspapers (ProQuest)
British Library Newspapers (Gale)
British Periodicals (ProQuest)
Digital Transgender Archive (College of the Holy Cross)
Irish Times (ProQuest Historical Newspapers)
LGBT Magazine Archive (ProQuest)
LGBT Thought and Culture (Alexander Street Press)
New York Times: 1851- (ProQuest Historical Newspapers)
Nineteenth Century UK Periodicals (Gale)
The Come Out Archive
Times (London) Digital Archive, 1785-2019 (Gale)
Washington Post (ProQuest Historical Newspapers)