Question: How many Orthodox Jews lived in Eastern Europe in 1939?
Answer: I was not able to find details on how many were Orthodox, as that is a rather subjective term. However, according to historian Lucy Dawidowicz, there were over 7.5 million Jews in Eastern Europe (9 million total in all of Europe). Again, I’m not sure how many were “Orthodox”, but I think that the majority in Eastern Europe were affiliated with Orthodox Judaism in some form, even if they were not all observant, particularly in Poland and Hungary.
Yitzchak Kolakowski