Dillingham Commission

The United States Immigration Commission was a bipartisan special committee formed in February 1907 by the United States Congress, to study the origins and consequences of recent immigration to the United States. It was a joint committee composed of members of both the House and Senate. It was known as the Dillingham Commission after its chairman, Republican Senator William P. Dillingham of Vermont.

The Commission ended its work in 1911, concluding that immigration from southern and eastern Europe posed a serious threat to American society and culture and should be greatly reduced in the future. The Commission proposed the enactment of a "reading and writing test as the most feasible single method of restricting undesirable immigration"

The Commission's overall findings provided the rationale for sweeping 1920s immigration reduction acts, including the Emergency Quota Act of 1921, which favored immigration from northern and western Europe by restricting the annual number of immigrants from any given country to 3 percent of the total number of people from that country living in the United States in 1910. The movement for immigration restriction that the Dillingham Commission helped to stimulate culminated in the National Origins Formula, part of the Immigration Act of 1924, which capped national immigration at 150,000 annually and completely barred immigration from Asia.

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