Jewish settlement in Germany dates to the 4th century and continued throughout successive centuries, resulting in flourishing communities, with an active and intellectual life. In the medieval period, the cities of the Rhineland, Cologne, Mainz and Worms, became outstanding centers of Jewish life and learning.
Beginning with the First Crusade (1096 CE), Jews in the German lands suffered severe persecution, massacres and expulsion, including most notoriously the mass killings of Jews in Speyer (Spira), Worms and Mainz. In 1349, Jews throughout Europe were murdered after being accused of causing the “Black Death” pandemic, including thousands in Mainz, Cologne, and Erfurt, among other German cities and towns. Many Jews fled eastward, taking with them the Yiddish language that first developed in Germany. In the 17th century, conditions improved, and in the 19th century, Jews were granted emancipation, which found official expression in the 1871 Constitution.
It was the German Jewish philosopher Moses Mendelssohn (1729-1786) who laid the foundation for the Haskala, the “Jewish Enlightenment,” which was to have a profound impact on Jewish thought. In fact, much of modern Jewish thinking originated in Germany. The Jewish Reform/Liberal religious movement was founded in Germany by Rabbi Abraham Geiger, and others in the early nineteenth century, and spread to other parts of the Diaspora. The roots of modern Orthodoxy can also be traced back to such German Jews as Rabbi Samson Raphael Hirsch in Frankfurt and Dr. Azriel Hildesheimer in Berlin. Conservative/Masorti Judaism was also conceived on German soil by Zacharias Frankel, who headed the Jewish Theological Seminary in Breslau (today Wroclaw in Poland).
The Jews of Germany attained great success in all walks of life, including commerce, industry, art, and science. German Jewish Nobel Prize laureates between 1900 and 1933 included Paul Ehrlich (Medicine, 1908), Richard Willstätter (Chemistry, 1915), Fritz Haber (Chemistry, 1918), Albert Einstein (Physics, 1921), Otto Meyerhof (Medicine 1922), and James Franck (Physics, 1925).
Some 12,000 Jews lost their lives fighting for Germany in World War I, a higher percentage than any other ethnic, religious or political group in that country. Jews were prominently represented among the founders of the Weimar Republic that arose out of the ashes of imperial Germany—and many regarded the Weimar years as the golden age of German Jewry. However, anti-Semitism continued to flourish, and the assassination in 1922 of Germany's Jewish-born Foreign Minister, Walter Rathenau (the scion of the family that founded the AEG concern), sent shockwaves through the Jewish community.