It is well known that the encounter between Crusaders and Jews caused severe devastation to the Jewish communities. More importantly, however, it left a traumatic legacy for generations to come: the aim of the Christians was to convert the Jews to Christianity by force. One of the outcomes of this experience was the manner in which the Jews chose to die rather than convert. Both in the Latin and Hebrew narrative accounts, the most striking aspect of these events was the way Jews killed their own families and then themselves in order to avoid baptism. From that time on Jews held this behaviour up as a model for emulation. They educated their children in the light of it and towards it, thereby building a system which prepared members of their communities for the day when they would undergo this supreme test of their faith. In this article I will explore the process of the socialisation towards Kiddush ha-Shem - dying for the sanctification of God's Name, the development and synthesis of that norm in the Jewish communities of northern France and Germany between the years 1100 and 1350; i.e. how Kiddush ha-Shem became part of the Jewish 'self image' and how it came to be perceived as a part of the self, rather than law.