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Finding Primary Sources - an Introduction

Primary Sources are found in a range of places, including:

  • in archives and cultural repositories
  • with families and organizations who created them
  • reproduced in books and publications
  • digitized and online

Cultural repositories with historic records and archives have been digitizing them and sharing them online for decades. What is online usually represents a small selection of the repository's records. If you find primary sources online, you can trace the materials back to their repository and see what additional materials are available. 

When you are starting your search for primary sources online, these are some things to consider:

  • Who may have created materials or collected materials on this topic? Where might their records live now?
  • What formats of materials may have been created about this topic? (letters, objects, published work, newspaper articles, maps, architectural drawings, oral histories, interviews, photographs, etc)

With this information, you can begin searching online to find where these materials currently live. Archives and cultural repositories often have collecting scopes that guide their collections. They might gather materials on a particular topic, on a geographic location, on a particular organization or community. Other tips include checking citations in published research on the topic. Which archives are researchers and scholars citing?

Link to Research Notebook

We've developed a form to walk you through the research process

We based this form on our own process of research. Research is an iterative process and can take a lot of time, and you might not find what you are looking for. Often when we are searching, we have to reconsider our research questions based on what materials we discover.

Primary Sources Online - Overview

Primary sources are available online in two different ways:

  • freely available on the Internet from cultural institutions (examples: Cal Poly's Online Archive, Calisphere, American Memory from the Library of Congress, Densho, SAADA). 
  • available via library databases (example: Tribune Archives, Historical Sanborn Maps) that may be used from any computer with access to the campus network. Off-campus access is limited to Cal Poly students, faculty, and staff. These are subscription databases that the library staff identify in collaboration with the community.

Primary sources are usually found in digital collections. Types of digital collections include:

Primary Sources - California - Selected

Primary Sources - US History - Selected

Here are some of my "best bets" starting places for starting archives research 

Primary source and archival materials covering topics such as art and architecture, performing arts, technology, and applied sciences from the Library of Congress

DPLA connects people to materials held within America’s libraries, archives, museums, and other cultural heritage institutions. All of the materials found through DPLA—photographs, books, maps, news footage, oral histories, personal letters, museum objects, artwork, government documents, and so much more—are free and immediately available in digital format.

Search and view newspapers from 1880-1922 and find information about American newspapers published from 1960 - present.

Free public access to collections of digitized materials, including websites, music, moving images, and nearly three million public-domain books.

SAADA digitally documents, preserves, and shares stories of South Asian Americans. SAADA is the largest publicly accessible archive of South Asian American History

Densho is a grassroots community organization that preserves and shares history of the WWII incarceration of Japanese Americans during World War II

Subscription primary source databases available at Kennedy Library

While many archives have digitized archival materials available for public free access online (like at Cal Poly's Special Collections and Archives), sometimes, archives materials are only available online through expensive paid subscription. Kennedy Library has primary source databases paid for by the library and your tuition. Access to these resources are limited to students, faculty, and staff at Cal Poly. 

You can browse and search these subscription databases through the library's list of databases

Here are a selection of these databases, searching "primary sources"