History /
Pole, Hungarian, two good friends [58]
The emotional link has not been broken even among extreme political conditions like the period of the Second World War when Germany invaded Poland, while Hungary was a close political (and later military) ally of Adolf Hitler's Germany.
Nope, it all goes back to the "extreme political conditions" after the First World War, namely the Trianon "Peace" Treaty. All our neighbours feel antipathy towards us. And antipathy is a very PC word here. The exceptions are the peaceful and lovely Croatia and Slovenia. And Austria, of course, our brother-in-law. :) Poland is totally out of question. I doubt anyone would be negative towards someone with a Polish nationality in Hungary.
Luckily, it all different when we are abroad. I've never had problems with Slovaks in England, and I would have no antipathy towards Serbians and Romanians, if I ever met them here. (Let's just leave our hostilities at home!)
About genetic backgrounds: in my origin, I am Slovak on my mother's grandparents' side. After the 150 years of the Turkish Occupation, Slovakian settlers had been brought into various parts of Hungary at the beginning of the 1700s to re-populate the abandoned areas. Old people are still bi-lingual in my region, they speak both the old Slovakian and the Hungarian language. But very few of the young generations can speak or understand Slovakian. I regard myself a Hungarian.
To put it in a nutshell: I don't think anyone really gives a toss about genetic origins in Central/Eastern Europe. It's more about speaking the language. Compare: you can be an Irishmen/-woman if you can't speak or understand Irish Gaelic. But you can't be a Hungarian, Slovakian, Serbian, Romanian etc. etc. if you don't speak the relevant language!
This is my experience, at least. I can be mistaken. Cheers.