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U.S. History

This guide is intended to help people doing research in the History of the United States of America, defined broadly. It is not intended to be comprehensive. The focus is on topics of research in History Department.

Subject Searching in Bobcat

Subject headings are specific vocabulary that the Library of Congress assigns to published material. You can search Bobcat for books and other materials related to historical research by subject heading. General subject headings in history follow a specific pattern: Place name -- Subject -- Subdivision -- Time period.

Place names:

Can be names of countries, regions, states, or cities.

Subject

Describes the particular emphasis of the item.

Subdivisions:

Describe the a narrower emphasis of the item.

Time period:

Refers to the years covered by the item. Time period designations vary according to place name as well as to subject and subdivision, and are not included for all headings.

The following examples illustrate possible subject searches for migration to and from Pennsylvania:

Geographic Subject Headings Broken Out
Place Name as Subject Subject Subdivision Time Period
Pennsylvania Emigration and Immigration    
Pennsylvania Emigration and Immigration Early works to 1800  
Pennsylvania Emigration and Immigration Germans  
Pennsylvania Emigration and Immigration History  
Pennsylvania Emigration and Immigration History 18th century
Pennsylvania Emigration and Immigration History 19th century
Pennsylvania Emigration and Immigration Periodicals  

Sometimes, however, you may find an alternate pattern, with a specific subject listed first, then a palace, either a subject or geographic subdivision or a time period, another subject, and a date range.  For example I have pasted in the first entries for anarchism in Spain:

Subject Headings with a Subject followed by Geography
Subject Place Subdivision/Time Period Subdivision Time Period Subdivision
Anarchism Spain        
Anarchism Spain 19th century      
Anarchism Spain 20th century      
Anarchism Spain Almería (Province) History    
Anarchism Spain Andalusia History    
Anarchism Spain Andalusia History 19th century  
Anarchism Spain Andalusia History 20th century  
Anarchism Spain Andalusia Periodicals    
Anarchism Spain Aragon      
Anarchism Spain Aragon History    
Anarchism Spain Asturias      
Anarchism Spain Barcelona      
Anarchism Spain Barcelona History    
Anarchism Spain Barcelona History 19th century  
Anarchism Spain Barcelona History 20th century  
Anarchism Spain Barcelona History 20th century Fiction
Anarchism Spain Barcelona (Province) History 20th century Congresses
Anarchism Spain Benalup de Sidonia History    
Anarchism Spain Benalup de Sidonia History 20th century  

Notice the last two entries are for the pueblo in Andalusia better known as Casas Viejas.  The Library of Congress subject headings do not give you complete geographical information and they persist in using the current official name for geographic locations.  Bear this in mind when you look for events (Siege of Leningrad is now "Saint Petersburg (Russia) -- History -- Siege, 1941-1944"), or counties that no longer exist (East or West Germany are plain Germany).

For more information, consult the Library of Congress Authorities online (see below) or the five printed volumes in Reference, Library of Congress Subject Headings (LCSH), which contains the subject headings used in BobCat and other library catalogs. Look under the place name or subject to see the appropriate subdivisions and time periods.

Library of Congress Authorities and Classification