Let’s start with the easiest definition of primary vs secondary sources. Primary sources are sources from where or when an event happened, or from a person who was involved in or witnessed an event. Secondary sources are sources from those who were not involved, were not there, and often did not live in that time.
The journal of a civil war soldier at Gettysburg would be a primary source about Gettysburg.
A newspaper article about the battle of Gettysburg would be a secondary source about Gettysburg.
But it can get more complicated. What about interviews? What about newspaper articles? They can both be both. An interview can be both primary and secondary in the same interview, but about different topics. A newspaper article could be either one. What about news bloggers? If they were in the event, then their blog post might be a primary source. How about a documentary?
When you’re focusing on ancient and medieval sources, the lines become even muddier. Often there are no direct primary sources, but the closest source is the primary source. Ancient Romans didn’t have a lot of primary sources about the Roman republic, so when historians write about the Roman republic, they use a lot of archaeological sources, and other ancient sources such as Livy who lived after the events. Julius Caesar’s books are frequently used sources, but he was an observer of the cultures he wrote about. Even in the colonial era, a lot of the primary sources for indigenous peoples are that of the invading Europeans.
There are a few things that are always secondary sources though. Journal articles, textbooks, reference books, and most monograph books. As for primary sources, well, there’s nothing that is always a primary source. A journal can recount rumor or an anecdote from a friend, an interview could contain third hand information.
When evaluating a primary vs secondary source, you have to be critical and careful. Each source requires an independent and thorough review, especially when studying historical time periods. The further back a time period, the muddier the primary/secondary line becomes.
Here are some easy evaluation tools. Regarding each source, ask yourself:
1) was this person involved in the event I’m researching?
2) was s/he a witness to that event?
3) does this account contain rumor or hearsay?
4) is this a legal document from the time period?
5) (if artifact) has this artifact been reliably dated to the time period?
For further information regarding primary and secondary sources see:
For the downloadable, pdf version of this guide click here: Primary & Secondary Source Guide.