• 47 History
• 12 African Americans
• 11 Study and teaching
• 10 Antiquities
• 10 Motion pictures
• 10 Political participation
• 9 Production and direction
• 9 Recording and reproducing
• 9 Sound
• 9 United States
• 9 Vocational guidance
• 8 History and criticism
• 8 Politics and government
• 7 Popular culture
• 6 Commerce
• 6 Ethnicity
• 6 Presidents
• 6 Territorial expansion
• 5 Economic conditions
• 5 Frontier and pioneer life
• 5 Politicians
• 5 Religious leaders
• 4 Appreciation
• 4 Constitutional history
• 4 Power (Social sciences)

• 88 Films Media Group
• 88 Films for the Humanities & Sciences (Firm)
• 41 Public Broadcasting Service (U.S.)
• 11 A&E Television Networks, LLC
• 8 Public Affairs Television (Firm)
• 7 Moyers, Bill D
• 3 4 Learning (Firm)
• 3 National Geographic Television & Film
• 1 Centers for Disease Control and Prevention (U.S.)
• 1 Connell Creations (Firm)
• 1 Digital Classics (Firm)
• 1 Driscoll, Emily V
• 1 Ellis Entertainment
• 1 Essence of History, LLC
• 1 Independent Television News (Great Britain)
• 1 Planet Pictures (Firm)
• 1 Sagal, Peter
• 1 Sunrise Media LLC
• 1 TMW Media Group
• 1 Take Off Multimedia
• 1 Video Education Australasia
• 1 Wichita Films
• 1 Worldwide Media (Firm)

• 88 English

• 1 Connecticut
• 1 Grand Coulee Dam (Wash.)
• 1 Iceland
• 1 Los Angeles (Calif.)
• 1 Newtown
• 1 San Francisco (Calif.)
• 1 Texas
• 1 West (U.S.)
• 1 Wyoming

Limit year range