This is a continuation of the info on your profile comments:
earlier immigrants from Northern Europe and the British Isles. Efforts were made to slow the flood by imposing a literacy test on those wishing to enter the U.S. Wilson twice vetoed these measures, but Congress overrode his veto, in 1917.
Suspected Russian anarchists were denied access to the country, and suspicions about foreigners spilled over in the Red Scare of 1919-20, when thousands were arrested for real or imagined revolutionary activity.
Immigration reform, sometimes known as the Emergency Immigration Act of 1921, was prompted by the news that in the preceding 12 months more than 800,000
foreigners had entered the United States. Congress responded by establishing the first quota system that provided for the following:
Immigration from a specific nation was limited to three percent of that nation’s population living in the United States, as reported in the 1910 Federal Census.
An overall maximum annual quota of 357,000 was imposed.
Hope this will help, my sources were my extensive collection of history books and some useful websites,
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