Ethnic Composition of the United States' Population in 1890
These statistics were also important because the Johnson-Reed Act of 1924 restricted immigration into the United States to an annual rate of 2% of the population of each nationality in 1890. Calculations for quotas were based on the national origins of the population, even natural-born United States citizens. Immigrants from Asia were completely excluded under the Johnson-Reed Act. The quotas under the law were altered by emergency provisions for displaced persons after World War II (1948 and 1950) and revision of Immigration Restriction legislation in 1952.