The first recorded instances of blood libel actually occurred in pre-Christian times, still leveled against the Jews, but by the pagan Greeks. In 2nd century A.D. it was leveled against Christians by pagan Romans. It wasn't until the 12th century that it was level by Christians against Jews; in 1144 in Norwich, England, a Christian boy was murdered just before Easter, and the local Jews were accused (with no evidence) of crucifying him in a mockery of what happened to Jesus. The legend spread from there, and in the 20th century has been picked up by Muslim anti-semites.

Some of the nonsense that went with the blood libel was that Christian blood was needed for Jewish men to replenish their blood supply, since they menstruated, and also that they needed to make up for the blood the lost from circumcision.

The blood libel accusation has also been made by some protestants against Roman Catholics in the 19th century, and against protestant missionaries by the Bulgarian Orthodox Church.

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