1921 Emergency Quota Law (An act to limit the immigration of aliens into the United States)
H.R. 4075; Pub.L. 67-5; 42 Stat. 5.
67th Congress; May 19, 1921.
You can find the full text of this law as a PDF here.
The objective of this act was to temporarily limit the numbers of immigrants to the United States by imposing quotas based on country of birth. Annual allowable quotas for each country of origin were calculated at 3 percent of the total number of foreign-born persons from that country recorded in the 1910 United States Census.
Exceptions to the quotas were made for government official and their families, aliens who were passing through the US or visiting as tourists or temporary workers, immigrants from countries in the Western hemisphere, and minor children of US citizens. The Quota Act also did not apply to countries with bilateral agreements with the US on immigration, or to countries in the Asiatic Barred Zone (as defined in the 1917 Immigration Act).
(Summary by Brenda Barrientes)
Congressional Debate on Immigration Restriction - Debate on the subject of immigration quotas based on national origins in the House of Representatives on April 20, 1921.
Eugenists Dread Tainted Aliens - A 1921 article from the New York Times.
Eugenics Laws Restricting Immigration - An essay linking immigration laws in the first quarter of the twentieth century with the eugenics movement.
'America would Lose its Soul': the Immigration Restriction Debate, 1920-1924 - A Master's thesis by Vilja Lehtinen, Department of History, University of Helsinki.