Sometimes when one population pushes into another population's area, some of the pushed into population gushes back into the void abandoned by the invading population. So there are some central asian type people in europe just as there are some european type people in central asia.
Also my family took advantage of a plague outbreak in Transylvania to hole up for a generation or two, I don't remember exactly when. People were already telling stories we could play into, though we didn't meet the people who inspired them.
*on that and several other occasions we clocked the rate at which our descendants became european, that is why we are moving our cousins here, because while Gramps's daughters were total rebels his granddaughters were different but not trying to oppose society and his greatgranddaughters were indistinguishable from the surrounding population, however we learned that this was adaptive because if we went back later it wasn't like we had never been there before and each subsequent trip caused people to share more and more of our own traits in the first and second generations, it could even happen in the future that we don't have to visit at all*
