The Hebrew Bible, a religious interpretation of the traditions and early national history of the Jews, established the first of the Abrahamic religions, which are now practiced by 54% of the world. Judaism guides its adherents in both practice and belief, and has been called not only a religion, but also a "way of life," which has made drawing a clear distinction between Judaism, Jewish culture, and Jewish identity rather difficult. Throughout history, in eras and places as diverse as the ancient Hellenic world, in Europe before and after The Age of Enlightenment (see Haskalah), in Islamic Spain and Portugal, in North Africa and the Middle East, India, China, or the contemporary United States and Israel, cultural phenomena have developed that are in some sense characteristically Jewish without being at all specifically religious. Some factors in this come from within Judaism, others from the interaction of Jews or specific communities of Jews with their surroundings, others from the inner social and cultural dynamics of the community, as opposed to from the religion itself. This phenomenon has led to considerably different Jewish cultures unique to their own communities, each as authentically Jewish as the next.
Try to answer this question if possible (otherwise reply "unanswerable"): Where have specifically religious Jewish customs developed?
unanswerable