It helps that it's seldom as simple as crossing a border (that may not have been the same border 200 years ago).
Yes. But once it gets foreign, then it's truely hard to find traces of the inheritance beyond. At least that's the case with me.
My grand-mother is from Frankfurt, her father is believed to have a Swedish father, but as he left the family and was not known. At least that's what my grand-mother who's still alive (she's 92 years old) tells me, but my mother seems to not fully trust the story and I have just no way to know as I don't have any other family in Germany. That's about all I know about my "German/Swedish" family. As for my other grand-mother who lived in Algiers, she's actually born in Paris, has grown in Algiers and then returned in Paris in 1962. Once she was alive, she was always talking about Algeria as "her country", even if she never came back after having been kicked out. What do I know about her parents, not much actually.
Then the rest of the family is in France, it's pretty easier this way: so we know they are from families based in Orleans and Burgundy. But well, I'm personnally born in Belgium, my brother and my sister are born in Switzerland, my nephews are born in Australia and the UK, my cousins live in Saint-Martin in the Caribbeans, and my brother in law is from Quebec.
So as you can see... we could also be pretty international in the Old Europe.
The good thing about that is that it makes us travel to see the family.