Broadly speaking, Ashkenazim are descendants of Jews who migrated (or were expelled by the Romans) from Judea to Mediterranean Europe (what we now call Italy, Greece and the Balkans). The population eventually expanded into Western, Central and Eastern Europe.
Ashkenazim and native Italkim and Romaniotes (basically the Judeans who stayed put in Mediterranean Europe) are not only more similar to each other genetically, but they also share many cultural traditions and customs. They both derive a lot of their traditions from the customs and traditions of ancient Eretz Yisrael (but wait, didn’t we all? Yes, but normative tradition is heavily based on the Babylonian Jewish mesorah as reflected in the Babylonian Talmud (the cultural and genetic progenitors of Sephardic Jewry). The Jews of Judea and Galilee had divergent customs that is reflected in a vast corpus of literature that is not as well known or studied, beginning, of course, with the Jerusalem Talmud and various midrashim, halachic works and lots of liturgical poetry).
So to recap, Ashkenazim and indigenous Greek (Romaniote) and Italian Jews obviously share common recent roots in Southern Europe.
As I said before, normative Judaism is based mainly on the Babylonian Jewish tradition. We have scant records of the customs of the earliest Ashkenazic Jews (the core again having been basically Southern Italian and Greek Jews), but by the time we have a decent ouvre of halachic literature from that region, the customs and traditions differ only slightly from the Babylonian tradition. Nobody knows exactly how it happened, but the Ashkenazim gradually let go of many of their unique Eretz Yisrael traditions and customs and basically became grafted into the Babylonian sphere. The great scholar Yisrael Ta Shma in his works on Ashkenaz (specifically “Minhag Ashkenaz Hakadmon” and “Hatefila Hashkenazit Bekadmuta”) felt that many of those abandoned traditions stayed but took on the authority of custom-minhag rather than halacha-required law.
Very early Franco-German Jewry followed customs that were not in line with Bavel. This dissipated gradually probably because of immigration of Babylonians (to Ashkenaz) and/or the education of young men in Babylonian academies. Still, they retained unique customs and traditions that are clearly not Bavli. It’s interesting to note that certain rabbinical clans in Ashkenaz (utilizing that term in the broad sense) still fiercely held on to these traditions even while their local communities weren’t following them. There were rabbinical clans who followed customs and traditions that were clearly at odds with the Bavli tradition. They often were no longer aware of the ancient origin of their familial traditions. Clans such as the French “Bnei Machir” were perplexed as to why their family tradition of challah did not follow the Bavli tradition; they did not explicitly point to the Yerushalmi either (even though it clearly derived from there). The question is, of course, why were only some traditions retained and others discarded. Aside from what I said before (Ashkenaz became absorbed into the Bavli orbit for various reasons), I would also like to draw an analogy to chasidic nusach Sefard. Chasidic nusach Sefard is an attempt to follow the Ari; the chasidim felt that the Sephardic Kabbalistic nusach was vastly superior to their previous Ashkenazic one. Now they should have gone all the way and changed everything. At the very least they should have adopted the Sephardic dialect. Why didn’t they? Perhaps a sense of nostalgia; people want to hold on to some vestige of their past no matter what.
There are many other examples where Ashkenaz seems to follow Eretz Yisrael rather than Bavel: The Talmud requires that a bride and groom recite seven blessings for seven successive days following their wedding (sheva brachot). However, in order to recite the blessings there must be a fresh face at each of the nightly gatherings. This is referred to as panim chadashot. What about Shabbat? Here we encounter a novel approach by the Ashkenazic sage Rabbi Isaac the Elder of Dampierre (1115–c. 1184). Rabbi Isaac writes that Shabbat is considered a “new face” and therefore the blessings can be recited even if there are no actual fresh faces in the audience. This, according to Ta Shma, is based on an obscure Eretz Yisrael midrash (and also apparently on a passage in the EY Masachet Soferim). This leniency regarding reciting blessings is virtually unknown in the Babylonian tradition but it is common in Eretz Yisrael and the early Ashkenazic ones. (It would also be appropriate to mention here the English medieval sage Rabbi Elijah of London [a disciple of the famed French medieval master Rabbi Jacob Tam] who wrote that he would liberally recite blessings on all positive commandments, e.g., standing up for the elderly et al; see also the Provencal sage Rabbi Manoah ben Jacob who writes that he is of the opinion that great men of every generation can and should innovate new blessings).
Jewish diasporas and traditions never fit neatly into a box. When we talk of Franco-Germany, does it for instance include Provence—a region where Jews were highly influenced by Sephardic-Babylonian traditions as well as maintained its own unique ones? And then we have North Africa, where Jews followed a multiplicity of traditions.
*By the way, I sometimes talk about how the Eastern European Jewish diaspora is a hodgepodge of many previous Jewish diasporas; I particularly like to focus on the imprint that Sephardic Jews left on it. This does not mean that I think that Sephardic Jewish genetic influence is a huge factor (although the cultural influence was pretty big); I just chose to focus on it because it interested me (I casually threw out a figure of 20%, i.e., 20% of Eastern European Ashkenazic Jews are descended from Sephardic Jews who migrated to various parts of the late and unlamented Ottoman Empire). I hope I have made myself clear on that.*
Joel S. Davidi Weisberger runs Channeling Jewish History. You can find it on various social media platforms including Facebook and Twitter. He can be reached at [email protected]