Two very old and very discredited anti-semitic/zionist conspiricy theories deserve special mention.
The first is the so-called "Blood Libel." This entials the zccusation that Jews kidnapped and murdered the children of Christians in order to use their blood as part of their religious rituals during Jewish holidays. The tale is extraordinary and wholly illogical. If anything, it is a projection onto the Jews of the darkest aspects of Paganism and other primitive religious rituals.
No observant Jew would ever conceive of such acts. It is absolutely contrary to The Ten Commandments. In addition to the fact that it conttitutes murder, the use of blood (human or otherwise) in cooking is strictly prohibited by the kosher dietary law. Even nlood from slaughtered animals may not be consumed, and it must be drained out of the animal and covered with earth.
While animal sacrifice was part of the practice of ancient Judaism, the Old Testament itself, and all Jewish teachings since, portray human sacrifice as one of the evils that separated the pagans of Canaan from the Hebrews. Nevertheless, this story was started and repeated to serve political ends. It has no basis in fact.
The second is known as "The Protocols of the Elders of Zion." Although the exact origin is unknown, its intent was to portray Jews as conspirators against the state. In 24 chapters, or protocols, allegedly minutes from meetings of Jewish leaders, the Protocols describes the secret plans of Jews to rule the world by manipulating the economy, controlling the media, and fostering religious conflict.
It is certainly plausible that the Jewish Rothschild banking family were the inspiration for this global jewish conspiracy. For centuries the Rothschilds built a massive fortune through financial and political intrique. It is beyond doubt that this Jewish family did indeed exert substantial influence on a broad range of historic events, from small to large.
However, even a casual study of the family history reveals that the primary agenda of the Rothschilds was money and power for themselves. Any consideration of Jewish religion, welfare or identity was a distant cousin to this primary consideration.
In any event, in 1903, portions of The Protocols of the Elders of Zion were first published in a Russian newspaper. Following the Russian Revolution of 1917, anti-Bolshevik emigres brought the Protocols to the west. Soon after, editions circulated across the globe. An Arabic translation first appeared in the 1920s.
In 1921, the London Times presented conclusive proof that the Protocols were a fraud and a plagiarism. They had been drawn primarily from an 1864 French political satire that had nothing to do with Jews. The satire entitled "Dialogue in Hell Between Machiavelli and Montesquieu" was written as a protest against the Emporer Napoleon.
(1) http://goudsmit.pundicity.com/20344/the-political-purpose-of-anti-semitism
See also:
https://www.nationalaffairs.com/publications/detail/the-functions-of-anti-semitism