World War I and fears of the spread of radicalism produced enough pressure for Congress and the White House to act decisively to reduce immigration severely. Drawing on eugenics research and recommendations of the Dillingham Commission (1907-1911), this temporary measure limited immigration “scientifically” by imposing quotas based on immigrants’ country of birth. Annual 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 census. This approach to immigration restriction was immediately effective in reducing numbers although it caused disarray and confusion among aspiring immigrants who were abruptly denied entry because they traveled after annual quota allocations were filled.
CHAP. 8 .-An Act To limit the immigration of aliens into the United States
Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled . . . .
SEC. 2 . (a) That the number of aliens of any nationality who may be admitted under the immigration laws to the United States in any fiscal year shall be limited to 3 per centum of the number of foreign-born persons of such nationality resident in the United States as determined by the United States census of 1910… (b) For the purposes of this Act nationality shall be determined by country of birth, treating as separate countries the colonies or dependencies for which separate enumeration was made in the United States census of 1910…
SEC. 3 . That the Commissioner General of Immigration, with the approval of the Secretary of Labor, shall, as soon as feasible after the enactment of this Act, and from time to time thereafter, prescribe rules and regulations necessary to carry the provisions of this Act into effect . ‘He shall, as soon as feasible after the enactment of this Act, publish a statement showing the number of aliens of the various nationalities who may be admitted to the United States between the date this Act becomes effective and the end of the current fiscal year, and on June 30 thereafter he shall publish a statement showing the number of aliens of the various nationalities who may be admitted during the ensuing fiscal year…