| 1866 | William Sylvis establishes National Labor Union |
| 1869 | Knights of Labor organized |
| 1877 | Railroads cut workers' wages, leading to bloody and violent strike |
| 1886 | Samuel Gompers founds American Federation of Labor (AFL), Labor protest erupts in violence in Haymarket Riot in Chicago |
| 1889 | National Farmers' Alliance and Industrial Union formed to address problems of farmers |
| 1892 | Workers strike at Homestead steel plant in Pennsylvania |
| 1894 | Pullman employees strike |
| 1902 | Coal miners in northeastern Pennsylvania strike, Maryland is first state to pass workers' compensation law |
| 1903 | Women's Trade Union League (WTUL) formed to organize women workers |
| 1905 | Industrial Workers of the World (IWW) established |
| 1908 | Supreme Court upholds Oregon law limiting working hours for women in Mu11er v. Oregon |
| 1909 | Shirtwaist workers in New York City strike in the "Uprising of the 20,000" |
| 1910 | Strike at Hart, Schaffner and Marx leads to pioneering collective bargaining agreement |
| 1911 | Fire at the Triangle Shirtwaist Company kills 146 people, Frederick Winslow Taylor publishes The Principles of Scientific Management |
| 1912 | IWW leads strikes in Massachusetts and New Jersey |
| 1913 | Ford introduces the moving assembly line in Highland Park, Michigan plant |
| 1918 | Supreme Court strikes down federal law limiting child labor in Hammer v. Dagenhart |
| 1935 | Wagner Act grants workers collective bargaining (July) |
| 1937 | Auto Workers' sit-down strike forces General Motors contract (February) |
| 1938 | Congress sets minimum wage at forty cents an hour (June) |
| 1949 | Minimum wage raised from forty to seventy-five cents an hour |
| 1971 | President Nixon freezes wages and prices for 90 days (August) |