You're talking about immigrants who came over in the 1800s, probably late 1800s or maybe even early 1900s. Minnesota was not a state, or even a territory I believe, in 1776.
The discussion was about the early days of the US, when supposedly the different states were very different from each other according to some poster above. Back then, there were no immigrants from Serbia or Croatia; most everyone was from Britain. That's why English was the standard language of the nation, and all its states. Yes, later on, the US became very immigrant-friendly and had people move here from all over Europe plus other places, but we're talking about the early days here, both pre-revolution and for a time after. The different colonies were different from each other in some ways, mainly due to who founded them (some were founded by religious people who wanted a place to practice their weird religion without oppression or criticism, other were founded by people who wanted to take advantage of business and trade opportunities), but they were not as radically different culturally as the poster above alleged.
(As another aside, the far right's screaming about illegal immigration is one of the dumber things that I've ever seen in my life. After all, compared to the Indians and Eskimos we're all newbies.)
How did illegal immigration (aka colonization) from Europe work out for the Indians? Not too well. They probably wished they had had a better way of enforcing their borders.