- Coal miners2,772
- Coal mines and mining1,962
- United Mine Workers of America1,943
- International Union of Mine, Mill, and Smelter Workers1,542
- Coal mine accidents1,149
- Labor movement1,137
- Labor Unions1,088
- Strikes and lockouts--Coal mining1,057
- Coal mines and mining--Safety measures1,035
- Congress of Industrial Organizations (U.S.)1,034
- Coal mines and mining--Law and legislation1,008
- Communism576
- United Furniture Workers of America525
- Elections390
- Political Parties390
- Race relations363
- Ku Klux Klan (1915- )342
- Racism340
- Politics and Government339
- Coal mines and mining--Equipment and supplies326
