The Immigration Act of 1924, or Johnson–Reed Act, including the Asian Exclusion Act and National Origins Act, was a federal law that prevented immigration from Asia and set quotas on the number of immigrants from Eastern and Southern Europe. It also authorized the creation of the country's first formal border control service, the U.S. Border Patrol, and established a "consular control system" that allowed entry only to those who first obtained a visa from a U.S. consulate abroad.

Asian immigration to the United States refers to immigration to the United States from part of the continent of Asia, which includes East Asia, South Asia, and Southeast Asia. Asian-origin populations have historically been in the territory that would eventually become the United States since the 16th century. The first major wave of Asian immigration occurred in the late 19th century, primarily in Hawaii and the West Coast. Asian Americans experienced exclusion, and limitations to immigration, by the United States law between 1875 and 1965, and were largely prohibited from naturalization until the 1940s. Since the elimination of Asian exclusion laws and the reform of the immigration system in the Immigration and Nationality Act of 1965, there has been a large increase in the number of immigrants to the United States from Asia.