The Whig coalition drew strength from several earlier parties, including two that harnessed American political paranoia. The Anti-Masonic Party formed in the 1820s for the purpose of destroying the Freemasons. Later, anti-immigrant sentiment formed the American Party, also called the “Know-Nothings.” The American Party sought and won office across the country in the 1850s, but nativism had already been an influential force, particularly in the Whig Party, whose members could not fail to notice that urban Irish Catholics strongly tended to support Democrats.

Freemasonry, an international network of social clubs with arcane traditions and rituals, seems to have originated in medieval Europe as a trade organization for stonemasons. By the eighteenth century, however, it had outgrown its relationship with the masons’ craft and had become a general secular fraternal order that proclaimed adherence to the ideals of the Enlightenment.

Freemasonry was an important part of the social life of men in the new republic’s elite. George Washington, Benjamin Franklin, Andrew Jackson, and Henry Clay all claimed membership. Prince Hall, a free leather worker in Boston, founded a separate branch of the order for African American men.  However, the Masonic brotherhood’s secrecy, elitism, rituals, and secular ideals generated a deep suspicion of the organization among many Americans.

In 1820s upstate New York, which was fertile soil for new religious and social reform movements, anti-Masonic suspicion would emerge for the first time as an organized political force. The trigger for this was the strange disappearance and probable murder of William Morgan. Morgan announced plans to publish an exposé called Illustrations of Masonry, by One of the Fraternity Who Has Devoted Thirty Years to the Subject. This book purported to reveal the order’s secret rites, and it outraged other local Freemasons. They launched a series of attempts to prevent the book from being published, including an attempt to burn the press and a conspiracy to have Morgan jailed for alleged debts. In September, Morgan disappeared. He was last seen being forced into a carriage by four men later identified as Masons. When a corpse washed up on the shore of Lake Ontario, Morgan’s wife and friends claimed at first that it was his.

The Morgan story convinced many people that Masonry was a dangerous influence in the republic. The publicity surrounding the trials transformed local outrage into a political movement that, though small, had significant power in New York and parts of New England. This movement addressed Americans’ widespread dissatisfaction about economic and political change by giving them a handy explanation: the republic was controlled by a secret society.

In 1827, local anti-Masonic committees began meeting across the state of New York, committing not to vote for any political candidate who belonged to the Freemasons. This boycott grew, and in 1828, a convention in the town of LeRoy produced an “Anti-Masonic Declaration of Independence,” the basis for an Anti-Masonic Party. In 1828, Anti-Masonic politicians ran for state offices in New York, winning twelve percent of the vote for governor.

In 1830, the Anti-Masons held a national convention in Philadelphia. After a dismal showing in the 1832 presidential elections, the leaders of the Anti-Masonic Party folded their movement into the new Whig Party. The Anti-Masonic Party’s absorption into the Whig coalition demonstrated the importance of conspiracy theories in American politics. Just as Andrew Jackson’s followers detected a vast foreign plot in the form of the Bank of the United States, some of his enemies could detect it in the form of the Freemasons. Others, called nativists, blamed immigrants.

Nativists detected many foreign threats, but Catholicism may have been the most important. Nativists watched with horror as more and more Catholic immigrants (especially from Ireland and Germany) arrived in American cities. The immigrants professed different beliefs, often spoke unfamiliar languages, and participated in alien cultural traditions. Just as importantly, nativists remembered Europe’s history of warfare between Catholics and Protestants. They feared that Catholics would bring religious violence with them to the United States.

In the summer of 1834, a mob of Protestants attacked a Catholic convent near Boston. The rioters had read newspaper rumors that a woman was being held against her will by the nuns. Angry men broke into the convent and burned it to the ground. Later, a young woman named Rebecca Reed, who had spent time in the convent, published a memoir describing abuses she claimed the nuns had directed toward novices and students. The convent attack was among many eruptions of “nativism,” especially in New England and other parts of the Northeast, during the early nineteenth century.

Many Protestants saw the Catholic faith as a superstition that deprived individuals of the right to think for themselves and enslaved them to a dictator, the pope, in Rome. They accused Catholic priests of controlling their parishioners and preying sexually on young women. They feared that Catholicism had the potential to overrun and conquer the American political system, just as their ancestors had feared it would conquer England.

The painter and inventor Samuel F. B. Morse, for example, warned in 1834 that European tyrants were conspiring together to “carry Popery through all our borders” by sending Catholic immigrants to the United States. If they succeeded, he predicted, Catholic dominance in America would mean “the certain destruction of our free institutions.” Around the same time, the Protestant minister Lyman Beecher lectured in various cities, delivering a similar warning. “If the potentates of Europe have no design upon our liberties,” Beecher demanded, then why were they sending over “such floods of pauper emigrants—the contents of the poorhouse and the sweepings of the streets—multiplying tumults and violence, filling our prisons, and crowding our poorhouses, and quadrupling our taxation”—not to mention voting in American elections?