A Black Mass is a ceremony typically celebrated by various Satanic groups. It has allegedly existed for centuries in different forms and is directly based on, and is intentionally a sacrilegious and blasphemous mockery of, a Catholic Mass. In the 19th century the Black Mass became popularized in French literature, in books such as Satanism and Witchcraft, by Jules Michelet, and , by Joris-Karl Huysmans. Modern revivals began with H. T. F. Rhodes' book The Satanic Mass published in London in 1954, and there is now a range of modern versions of the Black Mass performed by various groups. History Early Catholicism The Catholic Church regards the Mass as its most important ritual, going back to apostolic times. In general, its various liturgies followed the outline of Liturgy of the Word, Offertory, Liturgy of the Eucharist and Benediction, which developed into what is known as the Mass. However, as early Christianity became more established and its influence began to spread, the early Church Fathers began to describe a few heretical groups practicing their own versions of Masses. Some of these rituals were of a sexual nature. The fourth-century AD heresiologist Epiphanius of Salamis, for instance, claims that a libertine Gnostic sect known as the Borborites engaged in a version of the Eucharist in which they would smear their hands with menstrual blood and semen and consume them as the blood and body of Christ respectively. He also alleges that, whenever one of the women in their church was experiencing her period, they would take her menstrual blood and everyone in the church would eat it as part of a sacred ritual. Medieval Roman Catholic parodies and additions to the Mass Within the Church, the rite of the Mass was not completely fixed, and there were places at the end of the Offertory for the Secret prayers, when the priest could insert private prayers for various personal needs. These practices became especially prevalent in France . As these types of personal prayers within the Mass spread, the institution of the Low Mass became quite common, where priests would hire their services out to perform various Masses for the needs of their clients (Votive Masses)—such as blessing crops or cattle, achieving success in some enterprise, obtaining love, or even cursing enemies (one way this latter was done was by inserting the enemy's name in a Mass for the dead, accompanied by burying