• 50 History
• 38 Study and teaching
• 22 Battles
• 15 World War, 1939-1945
• 11 Politics and government
• 10 Depressions
• 8 Economic conditions
• 7 Deterrence (Strategy)
• 7 Military art and science
• 7 Military weapons
• 7 Political activists
• 4 Power (Social sciences)
• 4 Territorial expansion
• 3 Immigrants
• 3 Indians of North America
• 3 Industries
• 3 Labor
• 3 Reconstruction (U.S. history, 1865-1877)
• 2 Biography
• 2 Mechanics
• 1 American literature
• 1 Authorship
• 1 Booth, John Wilkes, 1838-1865
• 1 Broadcasting
• 1 Castro, Fidel, 1926-2016

• 85 Films for the Humanities & Sciences (Firm)
• 13 Infobase

• 85 English

• 47 United States
• 2 Former Soviet republics
• 1 Antietam (Md.)
• 1 Europe
• 1 Russia

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