Reform Judaism began in 18th-century Germany to promote assimilation into Germany society. It was influenced by the legal emancipation of the Jews in some Western European countries, and their acceptance by the Christian church. The 18th-century German philosopher Moses Mendelssohn translated the Hebrew Bible into German and encouraged secular education for Jews. In the 19th century this led to the opening up of Judaism to European culture, subsequently known as the Haskalah (enlightenment). The belief developed that Jews could follow the mainstream ways of German society and be absorbed into it, and that Judaism could evolve and change.

By the early 19th century some synagogues were being called temples, and services were no longer being said entirely in Hebrew. The Hamburg Temple began conducting services along the lines of the Lutheran Church, and in the USA the Pittsburg platform of 1885 stated that kosher laws, a belief in the future Messiah, belief in heaven and hell, and support for the return to Zion were no longer necessary.

In Britain, Reform communities became more conservative in the early 20th century, and Liberal Judaism was formed as a radical offshoot. Reform Judaism in Britain has now become less secularized. Congregants wear tallit (prayer shawls) at prayer, and much of the service is in Hebrew. Both Reform and Liberal Judaism receive rabbinic leadership from Leo Baeck College (London).