Current discovery methods for American archival and manuscript (AM) collections rely on four national databases, WorldCat, ArchiveGrid, Archive Finder and SNAC, to which repositories report their holdings in the form of 1) catalog records (similar to library catalog records for books) and 2) finding aids (typically collection summaries and detailed inventories listing the folders in a collection). Most AM catalog records are accessible via the four major databases. There are also numerous state and regional databases which typically offer full text searches of finding aids, many of which, but not all, are linked from or searchable in the national databases. Not all repositories report their records at all, and many finding aids exist only in paper in their home repositories. This system has evolved since the inception of the National Union Catalog of Manuscript Collections (NUCMC) in 1959. Alongside of this system there exist numerous online and digital subject guides to AM collections. All of these resources are discussed below, and the national database system is diagrammed in the accompanying chart.

Each of the major databases must be searched to find all available collections.  Even after the main collection of an individual’s papers is found, sets of outgoing letters and other material may be found in other peoples’ papers, and sometimes a single person’s papers are split up among multiple institutions. The four main databases also have differing search options which yield different results even within material occurring in multiple databases.  Finding all available collections can be a complex business, thus the rather extended and detailed nature of the following instructions. Successful searches depend, especially in WorldCat, on getting the search terms and limitations exactly right and on trying a variety of searches using slightly different terms and limitations.

As in any catalog search find the proper Subject terms for your topic and use them together with your keywords.  WorldCat, ArchiveGrid, and Social Networks and Archival Context Project (SNAC) use Library of Congress Subject Headings (LCSH).  Archive Finder uses two systems of its own.  You can search a likely keyword, then note the Subject terms occurring on pertinent records.  For example, the LCSH term for slave revolts is Slave insurrections.  You can search for categories of persons by using Subject terms: Physicists, Women authors.  Library of Congress Subject Headings explained. A list of Subject terms is available at Library of Congress Subject Headings PDF Files.

Try both natural and inverted forms of names, with and without quotation marks for phrase searching. For example:

  •  “Robert Frost”  -  “Frost, Robert”  -  Robert Frost

Additional Sources

While these four sources probably contain the bulk of AM records, many are not included.  We discuss several additional sources, including:

Four main databases containing AM collection records



WorldCat is an online catalog of materials (books, periodicals, films, recordings, manuscripts, etc.) from libraries and other repositories across the world, but with a heavy emphasis on North America. There is a subscription-based version as well as two options for free access, all of which are dealt with below.

WorldCat (FirstSearch version) allows for searching of the NUCMC records (1986- ) and also contains catalog records for non-NUCMC AM material contributed by member libraries.

 AM collections may appear in three different forms within WorldCat: original collections, microfilmed collections, and digitized collections. The different steps involved in searching for microfilmed and digitized collections are covered after the discussion of original collections.

A keyword search in WorldCat on a person's name will find both collections of your subject's own papers (which may well exist in several repositories) and letters written by your subject and occurring in their recipients' papers. You can also search for categories of persons by using subject terms: physics, physicists, women authors. Finding aids are often linked from the WorldCat record.

You can also limit a search geographically.  Thus, search as Subject keywords:

Birmingham and (Alabama or Ala).  The full state name and the abbreviation are both used in different Subject terms.  A list of the proper abbreviations is available.

Limit by repository state using Keyword: cp: Massachusetts

Remove punctuation and other symbols  (colons, parentheses) from search terms.

To search for AM in WorldCat, go to Advanced Search.  Put your search terms in a search box. Then you have two options for limiting to AM material (you must do both searches in order to cover all relevant materials, though the results will overlap to some extent).  Limiting is usually necessary because WorldCat contains millions of records for books and other media which normally overwhelm the AM records.

Search 1: Check Archival Materials at Limit type to: and search.

Search 2: Remove the check next to Archival Materials and then change Subtype limits from Any format to Manuscript. Adjust the menu of another search box to NOT Material Type and type in the box: Thesis/dissertation.  Theses and dissertations are tagged as both manuscripts and books and often clutter the results of topical AM searches.

In the first search, setting Limit type to: Archival Materials yields “mixed materials”, that is, typical sets of personal papers and organizational records, together with many scrapbooks. Excluded are individual manuscripts such as manuscripts of literary works, diaries, and other unitary items, usually tagged as manuscripts (which will be included in the second search). Much manuscript material is tagged as both Manuscript and Archival Material, but a good deal is only tagged as Archival Material or as Manuscript. Searching Archival Materials and Manuscript simultaneously will exclude much material, thus the need to perform two searches.

In searches on a topic (example, Subject: Psychology) you often retrieve numerous non-archival records even when Archival Materials (or Manuscripts) is checked, In these cases you can refine your search by adding in another search field:

Subject: sources OR diaries OR correspondence OR archives OR manuscripts OR "Personal narratives" OR notebooks OR records)

Or, in a Keyword field search:

(Psychology) AND (su:sources OR su:diaries OR su:correspondence OR su:archives OR su:manuscripts OR su:"Personal narratives" OR su:notebooks)

You can also use codes:

In a keyword field:

kw:search term AND (dt=mix OR mt:mss) NOT mt:deg

Use caps for AND, OR, NOT (small letters ok for FirstSearch). “dt:mix” limits to archival, or mixed, collections; “mt:mss” limits to individual manuscripts such as manuscripts of literary works, diaries, and other unitary items. Dissertations are usually tagged as manuscripts, so the “NOT mt:deg” excludes these.


At “Libraries worldwide that own item” there are frequently two locations given: that of the repository actually holding the collection and LIBRARY OF CONGRESS/NUCMC. “LIBRARY OF CONGRESS/NUCMC” indicating that a catalog record of the collection was sent to the Library of Congress for inclusion in the National Union Catalog of Manuscript Collections (see below under Archive Finder), but the collection itself is not at the Library of Congress.

When the WorldCat location is New York State Historical Documents, search for the particular location in New York State Library catalog, changing Library from ALL to HDI (Historical Manuscripts Inventory).


ArchiveGrid is a freely available database of AM collections world-wide, again with a heavy focus on the US.

ArchiveGrid contains all AM records in WorldCat (minus dissertations), plus thousands of finding aids contributed independently by libraries and archives. There are many more catalog records than finding aids. All of this material is searched together. Microfilmed and digitized collections are not generally included. Sometimes the WorldCat records found in ArchiveGrid are in simplified form.

Due to the inclusion of searchable finding aids, ArchiveGrid offers a finer grained search than WorldCat, while the catalog record searches in WorldCat yield a more focused set of collections. The finding aids linked from the WorldCat catalog records in ArchiveGrid are not searched; only the finding aids contributed by individual archives are searchable.  Searching the full text of finding aids allows discovery of topics, persons and organizations too minor in the collection to occur in the catalog record.  Searching a major topic, person or organization, say NAACP, will yield many records with relatively trivial occurrences of the name.  To isolate collections which contain the person/subject of interest as a major part of the collection, use WorldCat. Although many finding aids are available in ArchiveGrid and in the more local databases discussed below, many finding aids remain undigitized and must be consulted on paper.  Be sure to use both the proper Subject terms together with a variety of keywords for your topic.

Limit your searches to repositories in a particular state or city with searches of the form: slave location:massachusetts; slave location:boston. Note that location:massachusetts and location:boston must be lower case.  The How to Search page omits the colons taht are essential for the searches to work. Examples:

  • archive:Boston  (archives in Boston)
  • archive:Massachusetts Archives  (a particular archive)
  •  (archival collections about Cambridge)

SNAC (Social Networks and Archival Context)

SNAC (Social Networks and Archival Context) is a freely available database of descriptions of the creators (people or organizations) of archival collections, unlike Archive Finder, WorldCat, and ArchiveGrid, which contain descriptions of collections. Its focus is on creating a network of AM collections which for any particular person or organization link to the names of associated persons and organizations.

The SNAC Prototype at present holds several hundred thousand records and includes French and British as well as American repositories. SNAC includes many AM records from the public version of WorldCat. All the WorldCat AM records were loaded into SNAC about two years ago but have not been updated since then. Remember that these comprise largely records of original collections, not microform or digitized collections.

A SNAC record contains a biographical/institutional sketch (where available), links to collections and related resources, and to related persons, families and organizations, all harvested from finding aids provided by the collection repositories, WorldCat records and other sources. A unique feature of SNAC is a visualization of the relationship between the creator of that record's collection and all other persons/organizations within the SNAC network.

A considerable expansion of the SNAC contents is expected soon.

Searching a subject (e.g., “civil rights”) will lead to a results list of persons, corporate bodies, and organizations related to that term. This may be useful in discovering connections between entities that were not otherwise apparent.

A search in SNAC on Botanists and Massachusetts (like the search in WorldCat and ArchiveGrid above) yields results overlapping only slightly with the WorldCat/ArchiveGrid results. You can do a search on WorldCat subject terms, but not all records have them, and sometimes not all the Subject terms from WorldCat records have been included in SNAC records.

Sometimes the location is missing on the SNAC record, but the linked WorldCat record gives it.

Archive Finder

Archive Finder is an online, subscription-based database of archival materials in the US, UK, and Ireland.

Archive Finder contains two different sets of records:

1. National Union Catalog of Manuscript Collections (NUCMC). Starting in 1959, archival repositories sent catalog records of their collections to the National Union Catalog of Manuscript Collections at the Library of Congress. These were published in a series of volumes until 1993. From 1986 on, NUCMC also sent records to the WorldCat database (see below). Repositories that are not members of OCLC (the organization the produces WorldCat) submit records to NUCMC. Archive Finder searches the NUCMC records through 2010.

2. National Inventory of Documentary Sources (NIDS). Since the 1980s many repositories in the US and the UK sent finding aids to the National Inventory of Documentary Sources which created a catalog record with subject terms for each collection. These finding aids were put on microfiche. Archive Finder searches the NIDS catalog records which bear the reference number for the corresponding microfiche. The NIDS microfiche are available in many large libraries (WorldCat record; there are many additional WorldCat records for the components of NIDS). Bear in mind that not all repositories have submitted finding aids to NIDS, and those that have may have sent inventories of only a portion of their holdings.

Some of the finding aids in NIDS also occur in ArchiveGrid, but NIDS has many that are not available digitally in ArchiveGrid and vice versa. Unlike WorldCat, there are no records for microfilmed or digitized collections.

On the Collection Search screen, use the Collection Name search to find collections where your subject is the creator or main topic. However, letters and other items written by or about your subject may also be found in the collections of other people. To find those, use “All Keywords.” Collection searches can be limited by repository, city, or state.

NUCMC and NIDS each have their own subject term systems. Note the subject terms assigned to your topic and, if needed, repeat your search using the proper subject terms for each database. NUCMC subject terms may be browsed in the Index to Subjects and Corporate Names in the National Union catalog of Manuscript Collections, 1959-1984 (3 vols. Alexandria, VA: Chadwyck-Healey, 1994).

A Repository Search retrieves brief descriptions of repositories, not of collections. Repositories can be searched by city or state. Choose "Repository Holdings Keyword" to search repository holdings statements. There is no standardized subject vocabulary in the holdings statements, so try several terms.

Additional Sources

State and Regional Sources for Online Finding Aids

By no means are all available online finding aids in ArchiveGrid. There are several state and regional databases of searchable digital finding aids. Some finding aids also find their way into the state and regional general digital libraries and the Digital Public Library of America.

See also:  Guide to Archives Consortia


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,

  • all these words: Botanists
  • any of these words: archives manuscripts correspondence diaries scrapbooks sources letters

Also try:

  • all these words: botanists Hawaii
  • this exact word or phrase: “archival collections” “manuscript collections”

Also try (separately):

all these words: botanists  WITH this exact word or phrase: finding aid

all these words: botanists EAD

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

Google Primary Sources Search

Google has created a customized search for primary sources. Use the same terminology suggested for the Google Advanced Search (above) to customize your search. General subject or person searches without the “digital collections” etc. qualifiers will yield more results, but the results list can be a bit disconcerting by identifying items in isolation, without giving you an idea of the broader collection they are located in. As with other Google searches, there is no controlled vocabulary.

Subject Guides

Subject guides, compiled by experts in special areas, often list unreported collections. Printed subject guides can be found via library catalogs and WorldCat, using the appropriate subject terms. The subject terms applied to published subject guides are variable, but the following types of subject searches are often effective:

Anthropology and “archival resources”

“Electronic data processing” AND (archives OR manuscripts) AND (directories OR catalogs)

An incomplete list of subject guides arranged by subject is available.

Biographical Dictionaries

Often the easiest way to find the main collection of personal papers of a prominent person is to search in a biographical dictionary.  Only a few of biographical dictionaries note locations of personal papers. Two important examples are:

American National Biography. Available online and in print.

Dictionary of Literary Biography is a huge series of volumes offering biographical-critical essays on authors.  Coverage is international, with emphasis on English and American. Available online and in print.
The DLB is indexed by name in the Literary Index
--Includes numerous volumes on essayists, travel writers, literary biographers, historians, book collectors and bibliographers, major publishing firms, etc. as well as on literary authors.

Additional sources for biography in Finding Biographical Information.

Early (pre-NUCMC) Resources

Many guides to archival and manuscript collections were published before NUCMC began in 1959. Much of this information has been incorporated into the currently used resources, but some, especially records of collections in small libraries and historical societies, is only accessible via local catalogs or the pre-NUCMC literature. Philip M. Hamer’s A Guide to Archives and Manuscripts in the United States (New Haven, Yale University Press, 1961, xxiii, 775 p.) includes many of these records and provides a listing of earlier works. How much archival material is reported only in this early literature is unknown.

W.P.A Historical Records Survey State Manuscript Repository Guides

Some old guides that have fallen into obscurity may still occasionally be of use. The WPA Historical Records Survey guides of the late 1930s reported holdings for many repositories. Indexes to these guides include both personal name and topical entries, e.g., physicians. Many local people represented in these collections corresponded with prominent persons elsewhere, and these correspondents appear in the indexes. Items related to non-local individuals often occur in local autograph collections, which also are indexed. Many of the smaller repositories included have not been surveyed and reported since.  Others which reported their collections to NUCMC may not have reported their pre-1959 holdings.

The WPA guides may present difficulties as some of the repositories included no longer exist or have changed their names.  Some of the collections may have been transferred to other repositories.


Digitized versions of these guides may be searched in HathiTrust Advanced Full Text Search for <Guide depositories manuscript> in the Title field and your topic keywords in the Full text field, limiting to 1935-1945.  The California and Minnesota guides have apparently not been digitized.


A list of other WPA publications on archives and manuscripts may be found in Check list of Historical Records Survey publications: bibliography of research projects reports. No. 7 (110 pp.) in:

W.P.A. technical series. Research and records projects bibliography. No. 1-8. Washington, DC: Federal Works Agency, Work Projects Administration, 1940-1943, 8 v. 
HOLLIS Record with link to HathiTrust full text

Direct Inquiry

These procedures should yield most collections represented online, but many collections have no online presence.  Many repositories rely entirely on local paper finding aids or card catalogs, or may do so for their older collections. Most repositories have a backlog of unprocessed and unreported collections. Identify possible repositories from clues in biographical sources and inquire directly about collections. 

Archive Finder (see above) offers a Repository Search. Repositories can be searched by name, city, or state, and keywords. Other directories of archival repositories include:

American Historical Association Archives Wiki
United States Historical Societies Directory
Directory of State Archives

For personal papers of authors still in private hands, the WATCH: Writers and their Copyright Holders database can provide names and addresses of persons who may know where the papers are.

Hidden Collections Registry reports newly processed archival and special collections.