As far as I understand it, by the time of the destruction of the second temple in 70 CE, the Jews were mainly concentrated in the Fertile Crescent, with smaller populations in Rome, along the Persian Gulf and Yemen (though I may be wrong). I'm very curious to know what happened to them that they ended up in the backwaters of Poland and in England, and elsewhere in Europe. Thanks.
You'll see elsewhere in this thread a graveyard of deleted comments, and those comments reflect a principle issue in discussing Jewish history in Europe: repeating the historiographic problem of treating 'all jews' as a singular, undifferentiated community. That treatment, one which is arguably at the root of modern persecution which likes to cast Jews as a cabal committed to the destruction and/or enslavement of western society, was effectively founded in the 10th-11th centuries among ecclesiastical and clerical writings based on an older Christian idea of 'Jewish treason'.
The result is that many theories of Jewish presence in northern Europe (the Ashkenazi) tend to be politically inspired: complaints of medieval ecclesiastics about Jews creating of slave-trading networks; complaints of ecclesiastics about proselytizing Jews forcibly converting their employees/slaves/housekeepers; the more recent (and equally discreditable) theory of wholesale early medieval Khazar conversion to Judiasm. And even the seemingly less pernicious theory, but still reflecting a cultural stereotype more so than historical knowledge, is that of Jewish migration as a by-product of some essential mercantile imperative of Jewish culture.
Leaving aside the above disclaimer then we can turn to evidence.
Some have posted in response to this question that Jewish communities 'always existed' in Roman centres right up to Cologne, Germany. It is true that there were Jews in France and Germany in some Roman cities, but as Michael Toch writes, "Here too no continuity can be assumed from the Jews apparent in late antique centres like Cologne and Trier." There is no evidentiary basis in terms of archaeology, epigraphy/graves or documents to warrant speculation about Jewish communities existing continually from antiquity through the appearance of Jews in latter early medieval sources.
Historians now tend to see the Jewish presence in terms of 'two spheres': 'continuity' in mediterranean Europe, and 'discontinuity' in northern Europe.
What we can see, from some Latin but chiefly Arabic and Babylonian sources, is that the Sephardic Jewish community (as we call it now, from Sepharad) blooms in the southern half of Spain in the early 8th century CE, it would seem as a result of immigrations with the Arabic expansion from Northern Africa. Over the course of the next few hundred years of the early middle ages there is tremendous evidence of growth in these communities, some as Jewish 'towns' like Lucena, others where Jews were fully integrated in town and village populations. They were not a 'merchant class'; while not wanting to paint an idyllic picture, Arabic and Jewish writers, doctors, philosophers, judiciary, as well as labouring and mercantile classes, worked and lived side by side. Many of these Jews even bear Arabic names. It is here that some scholars point to the formation of a Jewish 'cultural profile' diffferent from the middle east was formed, and it is from this same 'demographic upswing' that historians believe carried Jewish life into Christian lands.
Why Jewish populations fell off and dwindled in places where they were represented in antiquity - like along the Mediterranean coast of France and in Italy - is attributed to the hostile treatment by the fairly zealous, Christianized 'invaders' like the Visigoths. But by the 9th century Jewish name appear in documents in Northern Spain and in the Mediterranean littoral: resurgent in Barcelona, Narbonne, Marseilles, Montpellier, Arles.
Gaul in the early middle ages (more or less 'France' as we know it now) poses a special problem to us in evaluating sources. We have a heavy dependancy on ecclesiastical sources such as Gregory of Tours. I think Toch sums this problem best with some good examples of the challenges:
there is quite a profusion of literary and legal sources: letters of Sidonius Apollinaris and Pope Gregory I, hagiography by Gregory of Tours and others, Gregory’s Histories of course, and the councils of the Septimanian and the Frankish church, altogether thirteen between 465 (Vannes) and 647/53 (Chalon-sur-Saône). This richness has uniformly been viewed as confirmation for a substantial Jewry established all over Gaul. However, a closer look at the sources, both as literary genres and by themselves, raises some questions. Among the stock miracles performed by holy bishops we find the conversion to Christianity of the Jews of their town. Given the widespread Augustinian notion of the Jews as the proverbial unbelievers but eventual witnesses to Christian truth, making them see the light is indeed a feat worthy of a holy bishop and clear proof for his saintliness. In addition, such performance heals dissent and re-establishes harmony within the city, yet another rhetorical task of hagiography pointed out by recent scholarship. This double purpose also animates the hagiographic accounts of Jews lamenting the dead bishop of their town. In a similar vein, they are made advocates for the saint’s power, for example when one Jew’s sarcasm sets in profile a healing miracle performed by St Martin at Bordeaux. On the strength of these texts the existence of organised communities has been asserted for a number of places – Tournai, Paris, Nantes, Tours, Orléans, Bourges, Bordeaux, Uzès. Unconfirmed by other evidence, such literary devices are hard to accept as speaking of actually existing Jews. In consequence, the notion of an early medieval settlement by Jews of central, western and northern Gaul is untenable, with the possible exception of Clermont. This does not rule out occasional appearances of individuals in these regions.
In the 7th and 8th centuries, subsequent to the rather large base of polemical and hagiographic works of writers like Gregory of Tours, there is almost no mention of Jews in Frankish sources until the Carolingians. In Charlemagne's time we get a few indications of Jewish life in his court and in references to travelling merchants, but not communities. Jewish 'communities' start to appear in late Carolingian sources (9th century CE), which seem to suggest immigration from the mediterranean littoral up the Rhone river into central France and by the late 10th and early 11th centuries clearly identifiable communities in the east and west of France.
For Germany we have similar evidence for Metz and Mainz in the 9th and 10th centuries and by the eleventh centuries (famously) there are large 'structured' communities in Trier, Cologne, Worms, Prague, inter alia.
The Jewish community in England appears to be the result of Norman conquest.
As to why did Jewish communities grow and move?, well, let's look at historiographic criticism based on where I started this post:
One view has hitherto dominated the understanding of Jewish livelihoods in the early Middle Ages: privileged and protected by rulers, uniquely equipped by their Talmudic law, community organisation and family ties, as well as by inbred inclination and/or the Diaspora experience, Jews were the proverbial long-distance traders connecting Europe with the Middle East and Muslim Spain. In the earlier period they are thought to have done so along with other Orientals; from the Carolingian period and into the eleventh century on their own. For many scholars they even possessed a veritable monopoly over commerce, particularly in the slave trade. This notion has to be discarded. It is clearly tied to contemporary (nineteenth- and twentieth-century) polemics and apologetics. It assumes a system and purpose where none existed. Its documentary basis is exceedingly thin and lends itself to a more convincing, even though less glamorous interpretation.
For every instance of Jewish merchant activity we can cite between late antiquity and 1000 CE, we can equally cite landed Jews, farming Jews, labouring Jews (either in the field, or as artisans) and physician Jews. Non-Jews worked for Jews, and vice-versa.
Again, we need to look at the southern and northern 'spheres' of experience for some insights...which I hope to get to in a followup post this evening as we move into the high middle ages.
For the moment I can recommend:
Michael Toch, The Economic History of European Jews: Late Antiquity and Early Middle Ages (Brill, 2012)
Robert Chazan, The Jews of Medieval Western Christendom, 1000-1500 (Cambridge, 2006)
Robert Chazan, Reassessing Jewish Life in Medieval Europe (Cambridge, 2010)
RI Moore, Formation of a Persecuting Society: Authority and Deviance in Western Europe 950-1250 (Wiley, 2008)
As well as Michael Toch's essay 'The Jews in Europe 500–1050,' in the New Cambridge Medieval History Vol 1, from which I drew quotes for this post.
With regards to England, the first record of Jews living in Britain is after the Norman conquest in 1066. As Christians were prohibited by the Catholic Church from charging interest (usury), the Normans brought a small community of Jews to England in order to act as money lenders.
Although the community was small, barely reaching 5,000 in number, they gradually incurred the wrath of both the masses and nobility alike as many found themselves heavily in debt to Jewish moneylenders. It's not without irony then that Jews were pilloried for this reason, since they were essentially forced into money lending due to being barred from practically all other professional guilds and even from owning land.
In addition, with the Crusades featuring prominently in this period of history, a general sentiment of hostility to Jews, Muslims and Middle Easterners in general had become almost pervasive in English society. Antisemitic canards such as the blood libel and rumours of well-poisoning became widespread with several outbreaks of violence and persecution against Jews, notably the York pogrom of 1190 when the entire Jewish population of that city numbering 150 individuals were massacred.
In 1275, in a roundly popular move, King Edward passed a new statute which placed yet further restrictions on the Jewish community, including an outright ban on usury and absolving debtors of the need to repay loans, reducing many Jews to bankruptcy almost overnight. Other draconian restrictions followed, including:
Crucially though, Jews were for the first time allowed to own land for farming and along with a licence to trade, it gave them new opportunities to earn a living after the abolition of usury. Unfortunately, these harsh provisions along with widespread prejudice made this a particularly arduous task.
Things came to a crescendo in 1279, when the entire Jewish population of England (some 680 households) were arrested on charges of coin clipping, resulting in 293 executions in London. Finally, when it was discovered that many Jews had secretly continued to practice usury, King Edward issued an edict to permanently expel the Jews in 1290. The expulsion remained in force until the 17th century when Oliver Cromwell unofficially abolished the edict.
The new Jewish community in Britain grew slowly but steadily thereafter, with the population reaching 10,000 by the turn of the 19th century. Larger waves of immigrants arrived at the end of that century as a consequence of Russian persecution in the Pale of Settlement, with further immigration waves before and during WWII. Today the Jewish population of the United Kingdom is approximately 250,000, some 0.5% of the UK population.
Sources:
I would very much like to thank everyone for participating in this discussion. There were many very incisive comments and I have learnt a lot from you all. Thank you.