Labor unions form when workers unite to demand better treatment. What did labor unions in the early 20th century fight for?

They fought for the right to get more favorable work conditions and other benefits.

Explanation:

In the early 20th century, there was no such thing as a 40-hour week. Most workers would work for nearly 12 hours a day. People such as Theodore Roosevelt (in his 1912 Progressive Party run for president) campaigned for an 8-hour day, which was instated as part of the New Deal by FDR.

They often protested up to this time for more favorable work conditions. Some would protest about child labor too. These strikes were ultimately very influential, and they got the point across.

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