What caused anti-immigrant sentiment to increase in the united states during the 1800s?

The fact that the America was largely increased by farming in the 19th century

It was largely caused by an increase in farming efficiency due to technology. Advancements led to a surplus of labor, and the displaced workers saw the United States as a place that offered them new opportunities. Many immigrants faced a double culture shock, not only assimilating into an entirely new country but in many cases switching from agrarian jobs to urban work at the same time.

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