Primary and Secondary Sources in Historical Research: What Is The Difference?

Provides a clear, simple explanation of what a ‘primary’ source is and what a ‘secondary’ source is, with easy guidelines for distinguishing between the two.

One of the more confusing distinctions for history students at every level is that between ‘primary’ and ‘secondary’ sources. This page is intended to provide a clear definition of what constitutes each type of source and to provide simple guidelines for distinguishing between the two.

As with any rule, there are exceptions to those provided below. This is especially true when dealing with the history of recent years, within the past 100 years or so. But for purposes of study and research in history prior to 1900, these guidelines will, I hope, prove informative and useful.

What is a ‘Primary’ Source?

Generally, a primary source is one that was created at or extremely near the time of the historical events it describes. It is also usually the product of either the person(s) involved in the event or an eye-witness to the event. Primary sources can include not only handwritten documents and printed texts but also paintings, photographs, and physical artifacts.

Primary sources also include materials created at or near the time of the event but transcribed, translated, printed, and/or published at some later time, so long as the later version is an authentic and accurate ‘word-for-word’ rendering of the original. Handwritten documents, for example, are sometimes published in printed collections by academic presses in an effort to make them easier for researchers to access and to read. Numerous academic and research-oriented websites have also begun to post online printed transcriptions, sometimes called ‘calendars’, especially the excellent site British History Online.

Types of Primary Sources include:

  • A legal document such as a will, contract, or property deed relative to a person or event,
  • An individual’s diary or journal,
  • Letters between people and/or organizations,
  • Court and governmental records relative to a historical event,
  • Any of the above found reproduced ‘word-for-word’ in a modern printed form.

Examples of Primary Sources include:

  • The Last Will and Testament of Henry VIII (written ca. 1546),
  • The Diary of Grace Mildmay (d. 1620),
  • The Paston Letters or The Letters and Papers of Henry VIII,
  • The State Papers, Foreign and Domestic, for various reigns,
  • All of the above in modern printed and published transcriptions and calendars.

What is a ‘Secondary’ Source?

This category of sources is actual easier to define and to understand. The rules that govern it are also less subject to exceptions. A secondary source is any item that was created significantly after the events it describes or is related to, or that was created by someone who was not directly involved in or an eye-witness to the events. Secondary sources also include simple descriptions of primary sources that do not reproduce the original ‘word-for-word’.

Types of Secondary Sources include:

All biographies. A biography of an individual is never a primary source, though it may (or may not) be based on primary sources.
An account of an event written many years afterward. This can sometimes even include accounts written by eye-witnesses, especially if there has been a large lapse of time (e.g., a child’s eye-view of the French Revolution written only when the child had become a sixty-year-old man).
Textbooks, encyclopedias, and all other modern reference books.


As with any rule, there are exceptions to those that define the difference between primary and secondary sources. In general, the rules become more flexible as the historical event one is researching becomes more distantly removed in the historical past.

For example: a newspaper account of an event that occurred last week is not usually considered a primary source. If the event occurred during the American Civil War of 1861-65, e.g.: the Battle of Gettysburg, however, and the newspaper account was written near to the time of the event, let’s say one week after the battle, then one might consider that newspaper account to be a primary source. This would be especially true if the newspaper account was the only description remaining of the event.

But what if the event was the Battle of Thermopylae in 480 BCE and the account was written by Herodotus, a child of only four years of age when the battle occurred? Even though his account is both second-hand (he was not present at the battle) and written fifty years after the event, the fact that it is the earliest surviving account renders it a primary source.

Again, these are just general rules that often become more flexible as one discusses events of greater antiquity.

I’m confused….

Don’t feel bad! Even experienced graduate students in history sometimes get confused about the difference between primary and secondary sources and ‘argue’ about whether a specific source is one or the other.

But if you are working on a project for school and have questions about whether a specific source is a primary or a secondary one, feel free to contact me and I will try to help you figure it out, if I can.