You're wrong about the history of the United States. Dutch New Yorkers. Germans in Pennsylvania. (German is the predominant ethnicity of white Americans by the way.) French in Maryland. Lots of land purchased from French and robbed from Spaniards. And I didn't even mention the native peoples... All of these groups exist in significant numbers before the 1800s.

Since you're interested in around 1850, around there starts immigration from places like Ireland, Italy, Poland.. even a few Baltic people.

> robbed from Spaniards

They were Mexican by that point, right?

Depends where you are talking about. In the southwest or the west coast yes. I was thinking of Florida though, which was earlier. Though as I look that up maybe "robbed" is not the right word.

Then of course much later there was the war with Spain which resulted in caribbean US territories... This is becoming a big tangent though.

Here's a list of the top 100 American surnames. The majority of them are British/Scottish/Welsh: https://www.ssa.gov/oact/babynames/decades/century.html

No matter what you think, the British Isles are the ones who populated the country.

No matter what you think, white Americans are mostly German. Here is the top hit when I googled that:

"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...

> Here's a list of the top 100 American surnames. The majority of them are British/Scottish/Welsh

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.

People often adopted English surnames or Anglicized their names, especially around WWI (also when the huge number of German language newspapers mostly closed and even towns named after German places were renamed).