I have been tracing the origins of some of my childhood neighbors. I use ancestry.com, U.S. census records for 1940 and earlier, naturalization records, and other publicly available documents.
Following are examples of my findings:
A good friend of mine in high school had a grandmother living with the family. The grandmother did not speak English. She only spoke and understood Greek.
The parents of another classmate immigrated to the U.S. in the 1920’s. They recorded on their immigration form that they spoke Yiddish.
My near neighbors spoke German.
Another neighbor listed in the 1940 Census that she had been born in Sweden.
Another neighbor identified the German speaking part of Switzerland as her homeland.
Italy was identified as the home country by a number of people.
And Ireland was also identified by quite a number of people.
England was also favored by some.