Final answer:
The American labor movement, exemplified by the American Federation of Labor (AFL) and later the AFL-CIO, grew out of the necessity for workers' protections, achieving significant milestones under Samuel Gompers' leadership despite facing opposition and backlash.
Step-by-step explanation:
The American labor movement witnessed significant evolution from its early days of fragmented and local unions to the rise of the American Federation of Labor (AFL). Samuel Gompers, a key figure in labor history, founded the AFL in 1886, focusing on skilled workers and advocating for better wages and work conditions through collective bargaining and, as a last recourse, strikes. The impact of economic crises such as the Panic of 1873 and the Great Depression was dual-edged, often hampering labor organization efforts but also revealing the dire necessity for workers' protections, eventually leading to the AFL's growth and influence, despite the violent backlash unions sometimes faced from employers and authorities. By the mid-twentieth century, the AFL merged with the Congress of Industrial Organizations to form the AFL-CIO, becoming a powerful force representing a significant portion of American workers.