What are primary sources? Primary sources provide firsthand testimony or direct evidence concerning a topic or question under investigation.

They are usually created by witnesses or recorders who experienced the events or conditions being documented. Often these sources are created at the time when the events or conditions are occurring, but primary sources can also include autobiographies, memoirs, and oral histories recorded later.

Primary sources can be found in all of Yale’s libraries and museums as well as in online resources.  You can browse the collections of those libraries and museums or begin your search with examples of various formats.