Is Poland Central or Eastern European country?

[Roy]

The answer is neither. Poland is a proud Hyperborean country.

[Peterski]

(...)

Kanthak is more common in Thailand than in Germany: https://nazwiska.net/nazwisko-kanthak

Maybe the guy has Thai roots?

[Roy]

It was not German for centuries. The process of Germanization of this territory was very gradual and in case of some areas not completed even by 1944 (for example West Upper Silesia still had Polish majority).

It is the same in case of political belonging. For instance the city of Piła (Schneidemühl) was only German since the Partitions of Poland and then since year 1815.

Each area has a distinct history.

Mam świadomość że na Górnym Śląsku różnie bywało, no bo inaczej by nie było powstań śląskich chociażby
A co z Dolnym Śląskiem, Zachodnim Pomorzem, Warmią i Lubuskim? To nadal kawał ziemi

There were villages still speaking mostly Polish around Wrocław around ~1910.

[Roy]

^^
trough the centuries Russia was a part of European Tartaria , so only geographically in Europe

No wonder why they hang carpets on their walls.