Speaking from my own experiences and observations of either having lived, worked or travelled to many Eastern European countries, I believe there is a strong interest in Eastern European girls towards black guys- certainly big curiosity and fascination. Perhaps it's simply because there are still so relatively few black people in these countries.
My wife Nat who I met in Belarus is a rather typical such girl. I'm not sure she ever actually expected to experience a black guy living in Belarus, but the curiosity was there before we met. Compared to others' experiences, it was relatively easy to persuade her to give in to her curiosity once we were married and living in UK (and when she was sure that I was not looking for excuse to fuck other girls!).