The Anti-Masonic Party was the earliest third party in the United States. Formally a single-issue party, it strongly opposed Freemasonry in the United States. It was active from the late 1820s, especially in the Northeast, and later attempted to become a major party by expanding its platform to take positions on other issues. It declined quickly after 1832 as most members joined the new Whig Party; it disappeared after 1838.

Millard Fillmore was the 13th president of the United States, serving from 1850 to 1853, the last president to have been a member of the Whig Party while in office. A former member of the U.S. House of Representatives, Fillmore was elected vice president in 1848, and succeeded to the presidency when Zachary Taylor died in July 1850. Fillmore was instrumental in passing the Compromise of 1850, which led to a brief truce in the battle over the expansion of slavery.