Period newspapers can provide primary source information for specific eras in time.
Chronicling America is a project by the National Digital Newspaper Program (NDNP) to provide an Internet-based searchable database of historical U.S. newspapers. This includes a main page hosted by the Library of Congress and state repositories which receive funding from NDNP. Existing repositories from nearby states are also listed below.
State repositories will typically include a more in-depth collection of digitized newspapers. The list below shows a small sample of state newspaper programs. You will have to seek other states out, or contact the history subject librarian for assistance.
Many historical newspapers from around the world get digitized and uploaded to Internet Archive or HathiTrust by academic and historical institutions. Using these tools for this purpose works best when you have a specific newspaper you want to search for. Typically, a year's worth of papers will be cataloged together as a single volume, but that may differ between lending institution.