hoaxes or other false stories about Jews and Judaism
Antisemitic canards are "sensational reports, misrepresentations, or fabrications" that are defamatory towards Judaism as a religion or defamatory towards Jews as an ethnic or religious group. Since at least the Middle Ages, they have formed parts of broader Jewish conspiracy theories.
Some antisemitic canards or false accusations date back to the birth of Christianity, such as the allegation that the Jews are collectively responsible for the death of Jesus. In Medieval Europe, the scope of antisemitic canards expanded and became the basis for regular persecutions and formal expulsions of Jews in England, France, Germany, Spain and Portugal. During these times it was widely believed that Jews caused epidemics like the Black Death by poisoning wells. Jews were also accused of ritually consuming the blood of Christians.
Starting in the 19th century, the antisemitic notion that Jews were plotting to establish control over the world and dominate it by promoting capitalism and engaging in banking and finance first emerged. In the 20th century, further antisemitic canards alleged that Jews were responsible for the propagation of Communism and trying to dominate the news media. Those antisemitic canards which had political and economic contexts became political myths that were central to the worldview of Adolf Hitler and they persist to the present day.Holocaust denial is also considered an antisemitic conspiracy theory because of its position that the Holocaust is a hoax designed to advance the interests of Jews and justify the creation of the State of Israel.
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