Anti-Semitism: n; hostility to or prejudice against the Jewish race (The Oxford English Dictionary)
Although the Nazi's persecution was the largest act of discrimination against the Jewish race in history, anti-Semitism has been present for many centuries. The Jewish people have been pushed all over Europe, and persecuted in countries from Britain to Russia, since the end of the First Millenium. In history, we can see the many bloody events that led up to the Holocaust; the Crusades, in particular, saw heavy massacres of Jews.
During the First Crusade of 1096, Jewish communities in Germany were utterly destroyed, on a scale of complete extermination that the Holocaust never managed to match. Since then, the Jewish race has been discriminated against in almost every European country. However, in prewar Germany, before the Nazi race came to power, the Jews were enjoying a largely uneventful existence. Since 1848, they had benefitted from legal equality with other Germans, and over 12,000 Jews were not only allowed to fight for Germany, but died for Germany in the First World War.
However, beneath the surface, anti-Semitism was still rife. Before World War II broke out, and before the Holocaust began, Germany was in crisis - stuck in economic troubles and the Great Depression, unemployment was high and many Germans were feeling bitter and shamed by the signing of the Treaty of Versailles.
Life rapidly became worse for the Jews. As Hitler, released from prison, blamed them for Germany's troubles during his rise to power and in Mein Kampf, Germans became more and more prejudiced against the Jews. Pogroms (see 'Kristallnacht') became more common, and boycotts of Jewish-owned businesses occurred, encouraged by the Nazi party. The Jews became hated and blamed for every problem in German society, and the Nazis cashed in on this hatred with anti-Semitic laws (see 'The Nazi's Restrictions') that wiped out the Jew's freedom.
This anti-Semitism led to the Holocaust and the concentration camps. The hostility to the Jews and the indifference to their suffering displayed by many Germans allowed the Nazi party to, unopposed, introduce ghettos, camps and anti-Semitic laws.
An anti-Semitic march in 1935 with the passing of the Nuremberg Race Laws
Images of the Jewish boycott in 1933, when Jewish businesses were shunned