By 1920, a significant number of Koreans had immigrated to Hawaii and the United States mainland, but few if any of the immigrants' American-born children had set up their own households. This circumstance allows us to gain a fairly complete listing and enumeration of Korean Americans for that year's census, based on a search of the place of birth of the heads of households. By the time of subsequent censuses, many Korean American heads of households would report Hawaii, California, etc as their place of birth, so it is more difficult to obtain a comprehensive listing of Korean Americans for later years.

By this method, the total count of Koreans in the 1920 census, including non-Korean spouses, is shown to be 5,904. Eighty percent (80%) of these lived in Hawaii. Seventy-four percent (74%) of those reported as living on the mainland United States were in the Pacific Coast states (California, Oregon, Washington, Alaska).

The following are all derived from the 1920 census:

Koreans in the 1920 Census, by Region

Koreans in the United States (Hawaii excluded), 1920, Age-Sex Distribution

Koreans in California, 1920, Age-Sex Distribution

Average Age of Korean Immigrants, Year-by-Year