The blood libel against Jews originated in England in 1144 with the case of William of Norwich. The accusation that Jews used the blood of Christian children to prepare "matzos" for the Passover became a staple of Christian antisemitism of the Middle Ages, with the total number of recorded ritual murder accusations reaching 150. With the strengthening of standards of evidence in legal cases, the number of charges began to decline, and few blood libel cases reached European courts after 1772. Nevertheless, some instances of ritual murder accusation arose as late as the 19th century.