The Blaine Amendment was a failed amendment to the U.S. Constitution that would have prohibited direct government aid to educational institutions that have a religious affiliation. Most state constitutions already had such provisions, and thirty-eight of the fifty states have clauses that prohibit taxpayer funding of religious entities in their state constitutions.

Anti-Catholicism in the United States concerns the anti-Catholic attitudes which were first brought to the Thirteen Colonies by Protestant European settlers, mostly composed of English Puritans, during the British colonization of North America. Two types of anti-Catholic rhetoric existed in colonial society and they continued to exist during the following centuries. The first type, derived from the theological heritage of the Protestant Reformation and the European wars of religion, consisted of the biblical Anti-Christ and the Whore of Babylon variety and it dominated anti-Catholic thought until the late 17th century. The second type was a variety which was partially derived from xenophobic, ethnocentric, nativist, and racist sentiments and distrust of increasing waves of Catholic immigrants, particularly immigrants from Ireland, Italy, Poland, Germany, Austria and Mexico. It usually focused on the pope's control of bishops, priests, and deacons.