The factory system that developed around 1800 changed working conditions markedly. The employer no longer worked side-by-side with his employees. He became an executive, and, as machines took over manufacturing tasks, skilled workmen saw themselves relegated to the status of common laborers. In bad times they could be replaced by newcomers at lower wages.

As the factory system grew, workers began to form labor unions to protect their interests. The first union to hold regular meetings and collect dues was organized by Philadelphia shoemakers in 1792. Soon after, carpenters and leather workers in Boston and printers in New York organized too. Union members would agree on the wages they thought were fair, pledge to stop working for employers who paid less, and pressure employers to hire union members only.
 

Employers fought back in the courts, which commonly ruled that concerted action by workers was an illegal conspiracy against their employer and the community. But in 1842 the Massachusetts Supreme Court held that it was not illegal for workers to engage peacefully in union activity. This ruling was widely accepted, and for many years afterwards unions did not have to worry about conspiracy charges. Unions extended their efforts beyond wages to campaign for a 10-hour workday and against child labor. Several state legislatures responded favorably.