The words Popery (adjective Popish) and Papism (adjective Papist) are archaic words in the English language for Roman Catholicism, historically used by Protestants and Anglicans to label their Roman Catholic opponents, who differed from them in accepting the authority of the Pope over the Christian Church. The words were popularised during the English Reformation (1532-59), when the Church of England broke away from the Roman Catholic Church and divisions emerged between those who rejected Papal authority and those who continued to follow Rome. The words are now recognised as pejorative, despite having been in widespread neutral use in Protestant and Anglican writings until the mid-nineteenth century, including in some laws that remain in force in the United Kingdom.
Popery and Papism are sometimes used in modern writing as dog whistles for anticatholicism, or as pejorative ways of distinguishing Roman Catholicism from other forms of Christianity that refer to themselves as Catholic, such as Eastern Orthodoxy or Anglo-Catholicism. Papist was used in this latter way in 2008 by the Aristotelian University of Thessaloniki at a conference opposing ecumenism, and the word sees some wider use in the Eastern Orthodox Church.
The word was in common use by Protestant writers until the mid-nineteenth century, as shown by its frequent appearance in Thomas Macaulay's History of England from the Accession of James II and in other works of that period, including those with no sectarian bias.
The word is found in certain surviving statutes of the United Kingdom, for example in the English Bill of Rights of 1689 and the Scottish Claim of Right of 1689. Under the Act of Settlement of 1701, no one who professes "the popish religion" may succeed to the throne of the Kingdom of England and the Act continues to apply to the United Kingdom and all of the Commonwealth Realms; until the Succession to the Crown Act 2013 amended it with effect from 2015, the Act of Settlement also banned from the throne anyone who married "a papist". Fears that Roman Catholic secular leaders would be anti-Protestant and would be unduly influenced from Rome arose after all allegiance to the Pope was banned in England in the reigns of Henry VIII and Elizabeth I. Jonathan Swift (1667-1745), the author of Gulliver's Travels, employed the term in his satirical essay A Modest Proposal, in which he proposed selling Irish babies to be eaten by wealthy English landlords. Daniel Defoe wrote in the popular Robinson Crusoe (1719), near the end of the novel: "... I began to regret having professed myself a Papist, and thought it might not be the best religion to die with."
Similar terms, such as the traditional "popery" and the more recent "papalism", are sometimes used, as in the Popery Act 1698 and the Irish Popery Act. The Seventh-day Adventist prophetess Ellen G. White uses the terms "papist" and "popery" throughout her book The Great Controversy, a volume harshly criticized for its anti-Catholic tone.
During the American presidential election of 1928, the Democratic nominee Al Smith was labeled a "papist" by his political opponents. He was the first Roman Catholic ever to gain the presidential nomination of a major party, and this led to fears that, if he were elected, the United States government would follow the dictates of the Vatican. As of 2019, John F. Kennedy is the only Roman Catholic to have been elected President of the United States.
In early use the term appeared in the compound form "Crypto-Papist", referring to members of Reformed, Protestant, or nonconformist churches who at heart were allegedly Roman Catholics.Alexis Khomiakhov, a Russian lay theologian of the nineteenth century, claimed that "All Protestants are Crypto-Papists".
Although the term may simply imply a Romanizing influence, at times there have been individuals who have secretly converted to Catholicism, for example, James II of England, Bartholomew Remov and Yelizaveta Fyodorovich. Some people may later on openly convert, such as George Calvert, 1st Baron Baltimore, or secretly convert with reservations, such as John III of Sweden. The doctrine of mentalis restrictio was used to justify situations involving deceit.