Finding Primary Sources on the Open Web

There is no one way to find digitized primary sources on the Internet. The following offers methods for finding online historical resources which are more focused than a simple Google search. Most find items within digital collections. A few search the full text.

In most one cannot effectively limit to archival/manuscript sources.  Specific searches usually work better than broad topical searches.  Searches for proper names often yield good results.

The Digital Public Library of America

The Digital Public Library of America offers textual, visual, and sound resources contributed by numerous libraries, archives, and museums.  Searches catalog records, not full text.  Contains many individual items, such as letters and photographs, from digital collections.

Digital Libraries by State

These websites list hundreds of local, state, and regional resources. Each is different and some are better designed than others.  Very useful when your topic has a regional focus.

Advanced Google Searches

General Google searches may yield very many results, and it may take much sifting through the results in order to find relevant items. Using Google Advanced Search with specific search terms can help yield more focused results.

Within Google Advanced Search, use the “all of these words” and the “this exact word or phrase” to enter keywords for your subject, for example,

  • this exact word or phrase: climate change
  • any of these words: archives manuscripts correspondence diaries scrapbooks sources letters

This will yield a mixture of digitized full text and other material.

Also try:

  • all these words: Botanists
  • any of these words: "digital archive" "digital collection" "digital library" "online collection"

.Also try:

  • all these words: [Your topic words]
  • any of these words: cdm contentdm

"Cdm" or "contentdm" occur in the url of many digital collections

For any of these searches, use the “site or domain” box to search within just .edu, .org, or .gov sites.

Other Libraries' Research Guides are often Useful

In Google Advanced Search

  • all these words: library [your topic keywords]
  • any of these words: guides research resources
  • site or domain: .edu  [or or country domain, etc.]

Bielefeld Academic Search Engine

Bielefeld Academic Search Engine (BASE) searches metadata and some full text, from over 2000 sources of academic open access documents.  About 60% of the documents indexed are available full text.  The metadata searched is provided by the source and tagging is often inexact.  This is a vast collection of documents and has much not available elsewhere.
Use Browsing to narrow your search to subject area (e.g., Literature) or Document type (e.g., Manuscript, broadly construed).  Open Browsing and choose-Dewey Decimal (for Subject), choose major subject to see next finer level, twice.  After choosing View Records add a search term to the Subject Term or Document Type:


EROMM: European Register of Microform and Digital Masters searches its own database of records of printed and handwritten material in digital form or on microfilm from institutions worldwide and offers web search for such material.


Europeana: Cultural collections of Europe is the largest European search engine for digitized books, images, manuscripts, etc. Searches catalogs records of material contributed by numerous repositories.  Not full text searchable; links to full text.  Similar to the Digital Library of America

Lists and Guides for Digital Collections

General Digital Libraries

General Digital Libraries

Google Book Search, HathiTrust Digital Library and Internet Archives offer books and periodicals digitized from numerous libraries.  Only out-of-copyright, generally post-1923 books are fully viewable.  Each of these three digital libraries allows searching full text over their entire collections.

Google Book Search offers full text of, largely, pre-1924 books and periodicals, snippet views of, largely post-1924 books and periodicals digitized in libraries, and partial "previews" of books submitted by publishers.

HathiTrust Digital Library. Each full text item is linked to a standard library catalog record, thus providing good metadata and subject terms.  Thus a full text search of the whole database can be limited by title or Subject term.  The catalog can be searched separately.  Many post-1923 out-of-copyright books, especially government documents, are full text viewable. You can search within copyright books to see what page your search term is on.

Internet Archive now offers a full text search. Put your terms (phrases or personal names, in quotation marks (""), work best) in the search box and choose Text Contents.

The Online Books Page arranges electronic texts by Library of Congress call numbers and is searchable (but not full text searchable).  Includes books not in Google Books, HathiTrust, or Internet Archive. Has many other useful features.

Internet History Sourcebooks Project

World Digital Library offers primary source materials.

The Making of the Modern World offers full text searching of works on economics and business published from 1450-1914 from the Kress Collection of Business and Economics at the Baker Library, Harvard Business School and the Goldsmiths' Library of Economic Literature at the University of London Library. Includes material on commerce, finance, social conditions, politics, public health, trade and transport. A great deal of more recently acquired material in the Kress Collection is not included in The Making of the Modern World.

Harvard's Subscribed Databases by Subject

To find databases available via Harvard Library by subject, go to HOLLIS Databases, scroll down to Best Databases for… and open History, or other topic.  Refine your results set on the right.  For example, for historical resources relating to women, go to Subject Category, open Show More, open Women, Gender and Sexuality Studies.  Also look for research guides on your subject among the Harvard Library research guides (Open Guides by Subject).

Digitized Harvard Collections

Digital Collections at Harvard. Digitized versions of Harvard University Library collections.

Harvard Law School Library Digital Collections