Why were the Jews been hated so musch in Europe?

1. After the French Revolution, the process of "emancipation" began for the Jews during which they abandoned many traditional, isolated ways and joined as active and highly succesful members of mainstream society. At the same time, however, they continued to speak their own languages, lend money, marry only themselves, and consider themselves "Jews" before anything else ("German," etc.) Their success in all walks of life aroused the hatred and jealousy of the mainstrem society.

2. In the later 1800s, the eugenics movement began to talk about innate differences between races, and Jews were considered foreign born Semites rather than idealized white Europeans.

3. Many Jews were associated with socialist movements, making them unpopular with rival political ideologies.

4. The impression began to arise that Jews were responsible for several major historical events, including World War one, in a "conspiracy" to control the course of history.

These factors combined to create a general ambiance of anti-semitism throughout the 19th century, particularly among the poor and uneducated (Sartre famously mocked the knee-jerk anti-semitism of many middle class people). In the Dreyfus Affair in France, a loyal Jewish officer was evidently wrongly convicted of treason, highlighting the great social tensions at hand; in Russia, entire Jewish villages were often dislocated or terrorized in periodic pogroms.

It soon became clear that trouble was brewing for the Jews of continental Europe, with increasing social legislation passed against them and increasingly horrific rhetoric being used by the Nazi government as they were scapegoated for all social ills. The situation became so bad that William II, the former Kaiser of WW1 days, said that he was ashamed to be a German. As it became increasingly clear that a policy of state-sponsored xenophobia was at hand in Germany, the Anglo world (where many Jews had grown quite socially prominent and influential) drifted toward increasingly tolerant attitudes.

While most people knew that Jews were being oppressed in Europe and that very bad things were happening, the full horror of the Holocaust was only made evident after the war, at which point the western world was shocked out of its two thousand year old ambivalent relationship to Judaism (at least temporatily). 

============

 There are many places where you can find good material on this topic. Believe it or not, "alternative history" writer Harry Turtledove has written about it exensively, as has another author in the genre, Eric Flint. Both have web sites where this topic has been discussed - and eventually you will find some of their books informative, entertaining reading. You won't even know you're getting a history lesson!

Here's an overview to help you:

once the Roman Empire crushed a Jewish rebellion in 77a.d., the Jewish nation was dispersed. Jews went to three primary locations after that although there were many spots in which they lived. They went to Damascus and Baghdad, to Rome, and to Spain (then the Roman province of iberia). For a VERY long time, the Middle Eastern headquarters of Judaism was a great center of learning, while after the Moors conquered southern Spain in the 8th Century CE, Jews became welcome.

But as the 'dark ages" settled over most of Europe, the people became isolated and mired in ignorance. In most areas, the bishops and priests of the Catholic Church were the most educated people around - and at that time doctrine of the Church blamed Jews for the death of Jesus. This became the foundation for suspicion and hatred of the few Jews found in much of Europe at the time.

As an exiled people, Jews tried hard to keep to their faith and to their own community. Their various religious laws and the customs that arose around those tended to set Jews apart, while with very minimal intermarraige there were few of the family ties formed outside the Jewish people that marked most communities of the time.

This separateness both preserved Judaism and exposed Jews to increasing hostility and suspicion. Over the centuries many regions made it illegal for Jews to live there at all, or forced the Jews into closed communities called today "ghettoes." As the influence of craft and other guilds grew in the early Middle Ages, Jews were excluded from competing in many occupations. This left largely service work inside the ghettoes and such things as merchant trading and banking open to the Jews.

At the same time, many of the Jewish enclaves creaed after the Roman dispersal spread even further. While Christian Europeans made Jews unwelcome, Muslim people welcomed Jews for their learning and many other skills. And because family ties inside Judaism were kept in that exclusive community, soon the more enterprising families had relatives in far-flung, important locales. This fostered trading and banking.

Ultimately Jewish physicians, astronomers, mathematicians, merchants and bankers became influential in Christian Europe. Local lords, princes and kings found it convenient to use Jews to borrow money - especially when both Islam and Christianity officially frowned upon charging interest (called "usury") for loans.

At the same time, those influential people also found it inconvenient to repay what they owed, and at times incied riots and attacks on Jews in order to get out of their obligations. Frequently some horrid event such as the presence of plague or the foul work of criminals who murdered or abused children would be blamed on the Jews. At times in history, especially in south central Europe in the 160's, and later in the Ukraine in the 1800's, this led to massive attacks, or in the Russian term, "pogroms," against the Jews, and tens of thousands were slaughtered.

After the Black Death of the 1300's, some claimed that the plagues were caused because God was angry at Christians for tolerating Jews. This also led to terrible slaughter.

Oddly enough, it also led to centuries' worth of bad hygiene among Christians, and indirectly led to hundreds of thousands of deaths from typhus, dyentery, skin diseases and more. The Christians, noting that Jewish religious laws required frequent bathing and other acts of ritual cleanliness, and afraid of misunderstood consequences of certain bathing practices (such as pneumonia or getting waterborne parasite infections), made it a public requirement for people to be dirty! In the 30 Years' War, when marauding armies of mercenaries devastated most of Western Europe, "clean" people who bathed and washed their clothing were considered Jews and killed just because of it.

Horrible claims were made about Jewish religious rituals during the 300 years when European Christians were also afflicted by such superstitions as fear of witches. one, that popped up far too often, was that Jews ritually killed and ate the bodies of Christian babies.

on the same day that Columbus landed in America, oct. 12, 1492, Isabella and Fredinand completed their conquest of Moorish Spain with a triumphal parade into the Alameda in Granada. It was a terrible doomsday for spain's Jews. They were expelled forcibly, or allowed to turn Christian, or killed in waves of public executions. Many Jews sought refuge in what is today Holland, and their relocation created for a time a new and brilliant Jewish community of culture and wealth.

A few years before, in 1453, Muslims conquered Constantinople, the captial of the Byzanatine Empire, and also opened a new era of wealth, freedom and influence for the Jews of the Levant. But by the 19th Century, all of these hopeful conditions had largely withered.

And after that, the Jews became hunted people for almost 150 years.

Source(s): EDIT; Thanks to KI for bringing up the Crusades. Added a LOT. also, one of the most important events of recent years was the Pope's formal apology to the Jews for the Catholic Church's attiude. Centuries too late, and many thousands of liters of blood too late, but still noteworthy.