What labor unions were the most successful? what did they gain?

In the history of America's trade and labor unions, the most famous union remains the American Federation of Labor (AFL), founded in 1886 by Samuel Gompers. At its pinnacle, the AFL had approximately 1.4 million members.

Because the union did not attempt to organize unskilled workers, it made few gains among new workers during the 1920s, when much of the growth of the economy took place in mass-production industries such as automobiles, rubber, chemicals, and utilities.

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They were eliminating problems caused by industrialization, urbanization, immigration, and corruption in government