Anti-Catholicism

Anti-Catholicism is generally understood as hostility, prejudice, or discrimination directed toward Catholics, as well as opposition to the Catholic Church, its clergy, and its adherents. Scholars commonly identify four broad categories of anti-Catholicism: political, involving concerns about Catholics' loyalty to the state; theological, rooted in disagreement with Catholic doctrines; popular, including fears and accusations that Catholics were heretics or potential traitors; and sociocultural, based on claims that the Church fostered or enabled forms of perceived immorality.

Following the Reformation, a number of majority-Protestant states, including England, Northern Ireland, Prussia and Germany, Scotland, and the United States, at various times incorporated anti-Catholic rhetoric and policies into their political and social life. These could include opposition to the authority of Catholic clergy (anti-clericalism), opposition to the authority of the pope (anti-papalism), criticism or mockery of Catholic rituals, and measures that contributed to religious discrimination and religious persecution against Catholics.

In the modern era, scholars have identified several populist movements in which anti-Catholic sentiment formed a significant component, including segments of Ulster loyalists in Northern Ireland during the Troubles and the second Ku Klux Klan in the United States. During the Troubles, anti-Catholic sentiment among some loyalist groups intensified in response to perceived links between Catholic communities and apparent Irish republican activity, as well as Catholic participation in the Northern Ireland Civil Rights Association, which lobbied for an end to discrimination against Catholics in multiple areas.

The second Ku Klux Klan, led for much of the 1920s by Imperial Wizard Hiram Wesley Evans, promoted what it termed "100 percent Americanism," linking its program to white Protestant dominance and presenting white Protestants as having a primary claim to represent the nation over other groups. In his 1926 essay "The Klan's Fight for Americanism," Evans portrayed Catholicism as a threat to the social and political order, asserting that "Protestantism must be supreme" and declaring that "Rome shall not rule America," which he framed as necessary to "establishing a land free of conscience." In both the Ulster and American contexts, anti-Catholicism often intersected with broader political, ethnic, and cultural conflicts.

Historically, Catholics living in predominantly Protestant countries were frequently suspected of conspiring and harboring political loyalties to the papacy that might conflict with loyalty to the state. In majority-Protestant countries that experienced large scale immigration, such as the United States and Australia, suspicion of Catholic immigrants and discrimination against them often overlapped with, or was conflated with, nativist, xenophobic, ethnocentric, and racist sentiments. For example, this included anti-Irish sentiment, anti-Filipino sentiment, anti-Italianism, anti-Spanish sentiment, and anti-Slavic sentiment, including specifically anti-Polish sentiment.

In the early modern period, anti-clerical governments in some states sought to limit the institutional autonomy and political influence of the Church. Measures could include contesting or restricting the pope's authority to appoint bishops, confiscating Church property, expelling certain Catholic religious orders such as the Jesuits, banning forms of Classical Christian education, and establishing state-controlled school systems as an alternative.