Blood libel or ritual murder libel (also blood accusation)[1][2] is an antisemitic canard[3][4][5] which accuses Jews of murdering Christian children in order to use their blood as part of religious rituals.[1][2][6] Historically, these claims—alongside those of well poisoning and host desecration—have been a major theme of the persecution of Jews in Europe.[4]

Blood libels typically claim that Jews require human blood for the baking of matzos which they eat during Passover, although this element was allegedly absent in the earliest cases which claimed that then-contemporary Jews reenacted the crucifixion. The accusations often assert that the blood of the children of Christians is especially coveted, and, historically, blood libel claims have been made in order to account for the otherwise unexplained deaths of children. In some cases, the alleged victims of human sacrifice have become venerated as Christian martyrs. Three of these – William of Norwich, Little Saint Hugh of Lincoln, and Simon of Trent – became objects of local cults and veneration, and in some cases their feast days were added to the General Roman Calendar.[who?] One, Gabriel of Białystok, was canonized by the Russian Orthodox Church.

In Jewish lore, blood libels served as the impetus for the writing of the Golem of Prague by Rabbi Judah Loew ben Bezalel in the 16th century.[7] According to Walter Laqueur:

Altogether, there have been about 150 recorded cases of blood libel (not to mention thousands of rumors) that resulted in the arrest and killing of Jews throughout history, most of them in the Middle Ages. In almost every case, Jews were murdered, sometimes by a mob, sometimes following torture and a trial.[8]

The term 'blood libel' has also been used in reference to any unpleasant or damaging false accusation, and as a result, it has acquired a broader metaphorical meaning. However, this usage of the term remains controversial, and Jewish groups object to it.[9][10][11]

https://en.wikipedia.org/wiki/Blood_libel