Fugitive Slave Act of 1850 in the context of "Fugitive slaves in the United States"

In the United States before 1865, a free state was a state in which slavery and the internal or domestic slave trade were prohibited, while a slave state was one in which they were legal. Between 1812 and 1850, it was considered by the slave states to be politically imperative that the number of free states not exceed the number of slave states, so new states were admitted in slave–free pairs. There were, nonetheless, some slaves in most free states up to the 1840 census, and the Fugitive Slave Clause of the U.S. Constitution, as implemented by the Fugitive Slave Act of 1793 and the Fugitive Slave Act of 1850, provided that a slave did not become free by entering a free state and must be returned to their owner. Enforcement of these laws became one of the controversies that arose between slave and free states.

By the 18th century, slavery was legal throughout the Thirteen Colonies, but at the time of the American Revolution, rebel colonies started to abolish the practice. Pennsylvania abolished slavery in 1780, and about half the states had abolished slavery by the end of the Revolutionary War or in the first decades of the new country's existence, although, depending on the jurisdiction, this did not mean that all slaves became immediately free due to gradual abolition. Vermont — having declared its independence from Britain in 1777 and thus not being one of the Thirteen Colonies — banned slavery in the same year, before being admitted as a state in 1791.

The Compromise of 1850 was a package of five separate bills passed by the United States Congress in September 1850 that temporarily defused tensions between slave and free states during the years leading up to the American Civil War. Designed by Whig senator Henry Clay and Democratic senator Stephen A. Douglas, with the support of President Millard Fillmore, the compromise centered on how to handle slavery in recently acquired territories from the Mexican–American War (1846–48).

The provisions of the compromise included a provision that approved California's request to enter the Union as a free state, and strengthened fugitive slave laws with the Fugitive Slave Act of 1850. The compromise also banned the slave trade in Washington, D.C. (while still allowing slavery itself there), defined northern and western borders for Texas while establishing a territorial government for the Territory of New Mexico, with no restrictions on whether any future state from this territory would be a free or slave state and established a territorial government for the Territory of Utah also with no restrictions on if the territory would become a slave or free state.

Presidential elections were held in the United States on November 2, 1852. Democratic nominee Franklin Pierce defeated Whig nominee General Winfield Scott.

Incumbent Whig President Millard Fillmore had succeeded to the presidency in 1850 upon the death of President Zachary Taylor. Fillmore endorsed the Compromise of 1850 and enforced the Fugitive Slave Law. This earned Fillmore Southern voter support and Northern voter opposition. On the 53rd ballot of the sectionally divided 1852 Whig National Convention, Scott defeated Fillmore for the nomination. Democrats divided among four major candidates at the 1852 Democratic National Convention. On the 49th ballot, dark horse candidate Franklin Pierce won nomination by consensus compromise. The Free Soil Party, a third party opposed to the extension of slavery in the United States and into the territories, nominated New Hampshire Senator John P. Hale.

The fugitive slave laws were laws passed by the United States Congress in 1793 and 1850 to provide for the return of slaves who escaped from one state into another state or territory. The idea of the fugitive slave law was derived from the Fugitive Slave Clause which is in the United States Constitution (Article IV, Section 2, Paragraph 3). It was thought that forcing states to return fugitive slaves to their masters violated states' rights due to state sovereignty, and that seizing state property should not be left up to the states. The Fugitive Slave Clause states that fugitive slaves "shall be delivered up on Claim of the Party to whom such Service or Labour may be due", which abridged state rights because apprehending runaway slaves was a form of retrieving private property. The Compromise of 1850 entailed a series of laws that allowed slavery in the new territories and forced officials in free states to give a hearing to slave-owners without a jury.