Which parts of Europe did the Jews establish a relatively large community? As far as the old story goes (and my meagre understanding of it), the Romans dispersed many Jews from Israel all over territories of Europe which they controlled.
But exactly which direction did they go into? I’m talking strictly about the European countries which they found themselves in . And I mean mass migration (i.e. large numbers of Jews who found themselves in foreign European places). I’m very interested in knowing how they assimilated (for example, which European language/languages they begun to speak first in large numbers). Which (modern-day) countries would these be in?
And how did the change in names (for example, from the original Hebrew names to let’s say a German name like Schwartz or Stein) come about and when (as in which period) was this assimilation at it’s greatest?
Final Q: How did the Jews who found themselves in a environment hostile to them manage to fund and then build synagogues between the 10th-19th centuries? The opposition to this move would have been great, so how did they do it?
Prior to the 19th century, German Jews didn’t use last names. Then Napoleon blew through Germany… in 1808 he decreed all Jews would take last names (He also officially freed them from Ghettos and did some other nice things like declare toleration of their religion.)
German Jews were free to make up their own names while Austrian Jews got names assigned to them. So there’s very little rhyme or reason.
Not sure when the Romans sent the Jews after the Bar Kochba rebellion (the last organized Jewish resistance). I understood that most Jews afterward settled in Egypt and North Africa (especially Alexandria), although no doubt some small communities were already in Europe.
Then, centuries later, the Jews came to Spain in large numbers with the conquering Arabs and Moors. From Spain, the Jews spread into France and Germany, and from there, to the east.
I know there were probably many other migration routes.
As for Jews taking German names, actually there was always a degree of name assimilation in every country the Jews lived in. The Spanish, or Sephardic Jews took on Spanish surnames (for example, wasn’t there a Sephardic Jewish boxer named Daniel Mendoza?) In Italy, there was a Jewish mystic named Moses Chaim Luzzato, I believe. Jews that moved to Eastern Europe ended up with far more Slavic-sounding than German-sounding names (Plotkin, Suharsky).
As for your final question, Xavier, Jews funded synagogues because they made money from their crafts and trades, like any other community.
As for encountering resistance, there is no doubt that the Church frequently made life difficult for the Jews and stirred up people against them, but there were always those in favor of keeping them around, if for their own purposes. This is a generalization, but I believe that the ruling institutions in European society (the nobility and the Church) often tolerated and often encouraged the presence of Jews, for reasons of prosperity (Jews, being forbidden by the Church to practice most trades, including farming, but conveniently allowed to practice moneylending when good Catholics were forbidden, therefore a Jewish community could stimulate the local economy) and also tolerated because the Jews were the perfect scapegoat for directing the anger of the poor away from the rulers.
Well, even before Jewish revolts, and before there Judea/Israel/Palestine was part of the Roman Empire, there was a pretty large Jewish population in Rome itself, in the Subura, which was Rome’s urban slum. In fact, the Jews of the Subura were big supporters of Julius Caesar.
As the Roman Empire spread, Jewish settlements spread with it, especially into the Balkans, France, Spain and the German cities on the Rhine. The Jewish presence in France Spain and Germany predated the Arab conquest of Spain. (In fact, persecution of the Jews by the Visigoths helped contribute to the Arab conquest.)
I see on preview that Captain Amazing has beaten me to it, but there was a fair-sized Jewish community in Rome itself several decades before the destruction of the Temple: Josephus ((Ant. XVII:11:1) mentions that some 8000 of them joined a delegation from Judaea that had come to ask for the removal of Archelaus (Herod’s son) from office, in 4 BCE.
There are various traditions about the origins of the Jewish communities of Spain, France, and Germany. Some date these as well to the destruction of the Second Temple (see commentaries of ibn Ezra and R. David Kimchi to Obadiah 1:20); others trace them further back, to the dispersal of the Jewish people after the destruction of the First Temple in 586 BCE; and there’s even a tradition that places some of the survivors of the civil war between Benjamin and the rest of the tribes (described in Judges chs. 20-21) in Germany, circa 1100-1200 BCE! AFAIK, though, the earliest extant documentation of Jews in Western Europe does indeed date to Roman times. (As an example, Rabbi Jacob Moellin, an important 14th-century halachic authority, records that he saw a gravestone in the Jewish cemetery at Mainz that was some 1100 years old.) Those communities remained pretty small, though, until about the 9th or 10th century.
IIRC, the dates for intensive Jewish settlement of various European regions are roughly as follows (although there were usually smaller communities in each area at earlier dates):
Italy - 1st-5th, 9th-20th centuries
Spain - 9th-15th centuries
France - 10th-14th centuries
Germany - 10th-14th, 16th-20th centuries
Austria - 12th-15th, 16th-20th centuries
Hungary - 12th-20th centuries
Poland and Lithuania - 15th-20th centuries
Ukraine and White Russia (Pale of Settlement) - 15th-20th centuries
Southeastern Europe - 15th?-20th centuries
I seem to recall that the early Jews in Italy adopted Latin as their native tongue, although I’m not quite certain about this. The later communities there mostly used Italian. In Spain, the Jewish vernacular was first Arabic (under Muslim rule) and later Ladino (under Christian rule); in France, it was Old French; in Germany, Austria, and all of Eastern Europe, it was Yiddish.