Anti-Judaism is an ideology and attitude that rejects the Jewish religion and Jewish people. In brief, anti-Judaism is the prejudice and hatred against Jews for religious reasons. As such, it defined for many centuries the lives of Jews in Christian Europe. It is different from antisemitism.
Because Christianity understood itself as emerging from Jewish roots, it needed to find ways to distinguish itself from Judaism. The biblical promise that God had chosen Israel as his people and to observe the divine commandments was reinterpreted by Christians that they, as the new community of Jesus the Christ, superseded Jews as the chosen people. The gospels in the New Testament describe Jesus’ death as occurring at the hands of the Romans, though supported by the Jewish Temple authorities. The passages were later employed by Christians as evidence that the Jews killed Jesus, the son of God—and, by extension, God himself (theocide). The resentment from such erroneous notions defined Jewish-Christian relations from the time of the Roman Empire’s adoption of Christianity as a state religion to modernity. Cultivated as the so-called supersession myth, it viewed Christianity triumphing over Judaism. Although rulers in Christian Europe endorsed humiliation, violence, and various forms of persecution against Jews, it must be noted that Christianity never advocated the genocide of Jews.
The presence of anti-Jewish sentiments also led to waves of expulsions of Jews from various countries in the Middle Ages. Many Jews forced to emigrate found shelter for several centuries in Poland (see also Polish Jews).
For a brief overview on anti-Judaism in Europe: