"Surname from the Baltic States" implies linguistic precision and specificity that "surname from the United States" does not convey and is in no means equivalent to. There is some vagueness in what I said but I left it there intentionally, people don't get crazy specific about personal details here usually. I was meaning to say I have a "foreign" surname.
For instance, I remember from History class that there were atleast 3 famous guys from the 1700s named "John Smith"
Since you're interested in around 1850, around there starts immigration from places like Ireland, Italy, Poland.. even a few Baltic people.
They were Mexican by that point, right?
Then of course much later there was the war with Spain which resulted in caribbean US territories... This is becoming a big tangent though.
No matter what you think, the British Isles are the ones who populated the country.
"German-Americans are America’s largest single ethnic group .... In 2013, according to the Census bureau, 46m Americans claimed German ancestry: more than the number who traced their roots to Ireland (33m) or England (25m). "
https://www.economist.com/news/united-states/21642222-americ...
Lots of people of other origins adopted English surnames because the British were the dominant early group, and then later people with British names were, even though not always of British descent.
So, now, sure, British surnames are dominant, but that's often not indicative of British descent.
What exactly is a native born American name to you? English origin? German? I honestly think you should be ashamed of what you wrote. It's deeply offensive to those of us with roots in other places.