Confusing on my lineage, Pomorski Hamot - my maternal side is 100% Polish

So I live in the USA, but my Paternal side is 100% greek and my maternal side is 100% polish, or so I was told. I took the ancestry DNA test and it come up with the following results:

Europe East 75%
Caucus 7%
Italy/Greece 5%
Iberian Peninsula 3%
European Jewish 3%
Europe West 2%
Middle East 2%
Asia South 2%
Scandinavia 1%
Great Britain <1%

Now this is the crazy part, So the Europe east isn't too surprising when i consider the Polish and then the Northern Greek (that I found out had Coratian, Albaina, etc.). Causcus is the same, must be a turkish mix from the greek. Italy/Greece is understandable as well as the middle east (turkish?)

What I am having trouble with is the Iberian Peninsula, Jewish, EU West, Scan, and GB.... Together these make up 10%. So doing some digging in the family tree I found quite a few German surnames on my grandfather's side. But then, I started talking to a Polish historian I know and he told me that I am not a real 50% polish..... I never put this together but my grandmother's maiden name was Hamot, and this is apparently a French Last name (which would explain the iberian peninsula).

Her father immigrated from Pomorski, Poland in the early 1900's. So my question is why did he have a French last name? If he was French why did he move to Poland? or his ancestors? I have heard that a lot of Poles moved to France in the 18th to 20th centuries but never the reverse? Can anyone shed insight to if this was a common practice?

Thank you!

What about Chopin's father?
There's nothing like pure nation and probably never has been. Everyone has some traces of 'foreign blood' in veins.

Cinek

The Napoleonic wars, particularly the ill-fated Russian campaign. Many soldiers stayed, not least because distances were greater then.

Hi there. I've been doing a bit of Googling and from what I can see, Harnot is a very rare name. There is some information stating that it was recorded in the Domesday Book. We have a derivation of the name in Ireland, spelled as Harnett which is not common but would be well known, Ireland being such a small country. I would say that your grandmother's French origins would be in the very distant past, back in the days of the Normans. I doubt very much that her father was French. The name, like many modern names has ancient origins but it could have come into your family at any time in the last 1,000 years! Would be difficult to trace. There are quite a few census records, given its rarity, for Harnot in the United States.

Sorry OP, I mis-read the name, I realize it's Hamot and not Harnot. Sorry about that! It might help somebody else though!