The Knights of Labor, the first mass organization of America’s working class, proved the chief beneficiary of labor’s newfound consciousness. The Noble and Holy Order of the Knights of Labor had been founded in 1869 as a secret society of workers who envisioned a “universal brotherhood” of all workers, from common laborers to master craftsmen. Secrecy and ritual served to bind Knights together at the same time that it discouraged company spies and protected members from reprisals.

Although the Knights played no active role in the 1877 railroad strike, membership swelled as a result of the growing interest in labor organizing that followed the strike. In 1878, the Knights abandoned secrecy and launched an ambitious campaign to organize workers. The Knights attempted to bridge the boundaries of ethnicity, gender, ideology, race, and occupation. Leonora Barry served as general investigator for women’s work from 1886 to 1890, helping the Knights recruit teachers, waitresses, housewives, and domestics along with factory and sweatshop workers. Women composed perhaps 20 percent of the membership. The Knights also recruited more than 95,000 black workers. That the Knights of Labor often fell short of its goals to unify the working class proved less surprising than the scope of its efforts. Under the direction of Grand Master Workman Terence V. Powderly, the Knights became the dominant force in labor during the 1880s.

The Knights of Labor was not without rivals. Many skilled workers belonged to craft unions organized by trade. Among the largest and richest of these unions stood the Amalgamated Association of Iron and Steel Workers, founded in 1876 and counting twenty thousand skilled workers as members. Trade unionists spurned the broad reform goals of the Knights and focused on workplace issues. Samuel Gompers founded the Organized Trades and Labor Unions in 1881 and reorganized it in 1886 into the American Federation of Labor (AFL), which coordinated the activities of craft unions throughout the United States. His plan was simple: Organize skilled workers such as machinists and locomotive engineers — those with the most bargaining power — and use strikes to gain immediate objectives such as higher pay and better working conditions. At first, Gompers drew few converts. The AFL had only 138,000 members in 1886, compared with 730,000 for the Knights of Labor. But events soon brought down the Knights, and Gompers’s brand of unionism came to prevail.