Though often noted that Crusaders slaughtered Jews en route to the Holy Land, it is not appreciated that the Jewish response turned a passive acceptance of martyrdom into active ‘Sanctification of the Name’ in which parents killed their children. Modelled on the Binding of Isaac and the cult of temple sacrifices, it sought to parody the crucified saviour of the Christians; it also reversed traditional rabbinical ethics, putting bloody self sacrifice at the heart of a new theology. This temporary transformation of Judaism changed the way in which Jews identified themselves in Christian Europe. The massacres were not minor digressions during the Crusades but key events.
