This is kind of a bunch of questions in one. These two terms get thrown around quite a bit in my classes but I'm still unclear on what exactly they mean, besides the fact that the Ashkenazim lived in Cental/Eastern Europe and the Sephardim in Spain. When and how did this distinction develop? How (if at all) relevant is it today and if isn't anymore when and why did it cease to be relevant? Are/were there any significant differences in religious practice between the two groups? I have also read that there was very little contact between the two groups in the Middle Ages and that when contacts increased due to the expulsion of the Jews from Spain this often led to conflicts and there being seperate Sephardi and Ashkenazi communities in the same city (this was only mentioned about a single city in an essay on a tangentially related topic, so I'm not sure how common this was). Why was there such a large divide between the two groups? If this is too much or too broad to cover in a single answer I'll also gladly take book recommendations on this subject.
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