Despite the Chinese exclusion act, which prohibited nearly all immigrants from China to the U.S, the country took in millions of new immigrants between 1880-1942. According to the Migration Policy Institute, immigrants made up nearly 15% of the U.S. population in 1910, a number that has yet to be surpassed. While immigrants were helping to power industrialization and bringing new culture and energy to the country, not everyone was happy about it.
At the time, some argued that immigrants were refusing or unable to integrate into the country and that they were a burden. Others claimed that they were taking jobs from citizens. Scholars note that the discussion about restricting immigration frequently overlapped with racist and cultural arguments about immigrants. Among the most vocal anti-immigrant voices were supporters of Eugenics, a debunked racial science that believed that people could be grouped into races and that some races were superior to others. Their arguments, laced in the language of science, had a profound impact on public and politicians attitudes towards immigrants.
Below are links to excerpts from the congressional debate over the 1924 immigration act from Facing History and Ourselves.
and a link to the Johnson-Reed Act, known as the 1924 Immigration Act.