Historically, Poland was both and is a transition region between central and Eastern Europe. Even when Poland was conquered, it was still the interface between

Historically, Poland was both and is a transition region between central and Eastern Europe. Even when Poland was conquered, it was still the interface between a central/western empire (Reich Germany) an eastern empire (Russia) and an in-between empire (Austria-Hungary) but I would certainly call a city like Białystok ‘eastern’, but not necessarily Warsaw, Krakow or Wrocław. The trouble is that what counts as ‘Eastern’ Europe can be demarcated by several large historical events (Mongols, flavour of Christianity, Communism, etc) so a definitive answer is hard to give.