Me and my partner are in the same boat as your wife - we're from the baltic states and when people are curious about our origins, they ask if we're polish or not. I don't really hold it against people, but having to reassert your own ethnicity gets tiring. Most people are not aware of the country I come from anyway.

As a side note of the knowledge the general public holds, it seems like the history knowledge people get out of highschool is severely lacking.