Ten Source Countries with the Largest Populations in the United States as Percentages of the Total Foreign-Born Population: 1970
According to the U.S. Census Bureau, the size of the foreign-born population in 1970 was 9,619,302.
Gibson, Campbell and Emily Lennon, U.S. Census Bureau, Working Paper No. 29, Historical Census Statistics on the Foreign-Born Population of the United States: 1850 to 1990, U.S. Government Printing Office, Washington, DC., 1999. This report available online.