Following the destruction brought by the First Crusade in 1096, two separate intellectual trends emerged among the Jews of northern Europe that would have a tremendous impact on generations to come: in France, rabbis began composing extended, in-depth commentaries on the Talmud known as Tosafot (additions); in Germany, a group of scholars focused their attention on prayer, mysticism, and ascetic practices. Members of the latter group came to be known as Hasidei Ashkenaz (the pious ones of German) or simply hasidim, although they should not be confused with today’s Hasidim, who originated in 18th-century Eastern Europe. Tamar Marvin examines their origins and beliefs:
It has long been debated by scholars what relationship the rise of the Hasidei Ashkenaz bears to the Crusade violence and to contemporary Christian pietistic movements, which it resembles in some aspects. It has been suggested that the movement was a response to the extreme violence of 1096, though some scholars stress continuities to pre-Crusade Ashkenazi Jewish mores and practices. More difficult to prove are contacts between German Christian monastics and the leaders of the Ashkenazi Jewish community, and [evidence of] these contacts remains compelling but circumstantial.
One of the notable factors pointing towards the Hasidei Ashkenaz as a response to the violence of the First, Second, and Third Crusade periods is their fixation on kiddush ha-Shem (martyrdom) and extreme practices of self-mortification.
More central, however, is the Hasidei Ashkenaz’s focus on God’s unity and incorporeality, coupled with a development of Divine intermediaries influenced by Saadya Gaon’s notion of kavod, an emanation of Divine Glory. This interest in intermediaries also led Hasidei Ashkenaz to develop a complex system of demonology and attendant magical rites to counter it. However, they maintained the immanence (presence in the world) of God Himself.
Read more on Stories from Jewish History: https://trmarvin.substack.com/p/chasidei-ashkenaz-the-rhineland-pietistic