the most secretive of which were the Hellfire Clubs, which were first reported in the 1720s. The most famous of these groups was the Order of the Knights of Saint Francis, which was founded circa 1750 by the aristocrat Sir Francis Dashwood and which assembled first at his estate at West Wycombe and later in Medmenham Abbey. A number of contemporary press sources portrayed these as gatherings of atheist rakes where Christianity was mocked and toasts were made to the Devil. Beyond these sensationalist accounts, which may not be accurate portrayals of actual events, little is known about the activities of the Hellfire Clubs. Introvigne suggested that they may have engaged in a form of "playful Satanism" in which Satan was invoked "to show a daring contempt for conventional morality" by individuals who neither believed in his literal existence nor wanted to pay homage to him. The French Revolution of 1789 dealt a blow to the hegemony of the Roman Catholic Church in parts of Europe, and soon a number of Catholic authors began making claims that it had been masterminded by a conspiratorial group of Satanists. Among the first to do so was French Catholic priest Jean-Baptiste Fiard, who publicly claimed that a wide range of individuals, from the Jacobins to tarot card readers, were part of a Satanic conspiracy. Fiard's ideas were furthered by Alexis-Vincent-Charles Berbiguier, who devoted a lengthy book to this conspiracy theory; he claimed that Satanists had supernatural powers allowing them to curse people and to shapeshift into both cats and fleas. Although most of his contemporaries regarded Berbiguier as mad, his ideas gained credence among many occultists, including Stanislas de Guaita, a Cabalist who used them for the basis of his book, The Temple of Satan. In the early 20th century, the British novelist Dennis Wheatley produced a range of influential novels in which his protagonists battled Satanic groups. At the same time, non-fiction authors like Montague Summers and Rollo Ahmed published books claiming that Satanic groups practicing black magic were still active across the world, although they provided no evidence that this was the case. During the 1950s, various British tabloid newspapers repeated such claims, largely basing their accounts on the allegations of one woman, Sarah Jackson, who claimed to have been a member of such a group. In 1973, the British Christian Doreen Irvine published From Witchcraft to Christ, in which she