Breakdown of Sectional Balance

The Fugitive Slave Act

The Fugitive Slave Act, passed in 1850, caused controversy and contributed to Northern fears of a "slave power conspiracy."

Learning Objectives

Explain the economic and political context of the Fugitive Slave Act and how Northerners responded to it

Key Takeaways

Key Points

  • The Fugitive Slave Act of 1850 was a reinforcement of a previous act of the same name passed by Congress in 1793 to provide for the return of slaves who had attempted to escape from their owners to freedom.
  • The new act made any federal marshal or other official who did not arrest an alleged runaway slave liable to a fine of $1,000.
  • In addition, any person aiding a runaway slave by providing food or shelter was subject to a six-month imprisonment and a $1,000 fine.
  • Slave owners only needed to supply an affidavit to a federal marshal to capture an escaped slave. Because suspected slaves were not permitted trial and could not defend themselves against accusations, many free African Americans were forced into slavery.

Key Terms

  • The Fugitive Slave Act: Laws passed by the U.S. Congress in 1793 and 1850 to provide for the return of slaves who escaped from one state into another state or territory.

The Fugitive Slave Act was passed by Congress as part of the Compromise of 1850 between Southern slave interests and the Northern Free Soil movement. The Fugitive Slave Act was one of the most controversial provisions of the 1850 compromise and heightened Northern fears of a "slave power conspiracy."


By 1843, several hundred slaves a year were successfully escaping to the North, making slavery untenable in the border states. The Fugitive Slave Act of 1793 required the return of runaway slaves by requiring authorities in free states to return fugitive slaves to their masters. However, many Northern states found ways to circumvent the Fugitive Slave Act. Some jurisdictions passed “personal liberty laws," which mandated a jury trial before alleged fugitive slaves could be moved. Others forbade the use of local jails or the assistance of state officials in the arrest or return of alleged fugitive slaves. In some cases, juries refused to convict individuals who had been indicted under federal law.

The Missouri Supreme Court held that voluntary transportation of slaves into free states, with the intent of their residing there permanently or definitely, automatically made them free, whereas the Fugitive Slave Act dealt with slaves who went into free states without their master's consent. Furthermore, the U.S. Supreme Court ruled in Prigg v. Pennsylvania (1842) that states did not have to offer aid in the hunting or recapture of slaves, which greatly weakened the law of 1793. These and other Northern attempts to sidestep the 1793 legislation agitated the South, which sought stronger federal provisions for returning slave runaways.

In response to the weakening of the original fugitive slave law, the Fugitive Slave Act of 1850 made any federal marshal or other official who did not arrest an alleged runaway slave liable to a fine of $1,000. In addition, officers who captured a fugitive slave were entitled to a bonus or promotion for their work, and any person aiding a runaway slave by providing food or shelter was subject to a six-month imprisonment and a $1,000 fine. Law-enforcement officials everywhere now had greater incentive to arrest anyone suspected of being a runaway slave, and sympathizers had much more to risk in aiding those seeking freedom. Slave owners only needed to supply an affidavit to a federal marshal to claim that a slave had run away. The suspected runaway could not ask for a jury trial or testify on his or her own behalf. As a result, many free black people were accused of running away and were forced into slavery.

Effects of the Fugitive Slave Act

The Fugitive Slave Act was met with violent protest in the North. This anger stemmed less from the fact that slavery existed than from Northern fury at being coerced into protecting the institution of Southern slavery. Moderate abolitionists were faced with the choice of defying what they believed to be an unjust law or breaking with their own consciences and beliefs, and many became radical antislavery proponents as a result. Many Northerners viewed the 1850 Fugitive Slave Act as evidence that the South was conspiring to spread slavery through federal coercion and force regardless of the will of Northern voters. In many Northern towns, slave catchers were attacked, and mobs set free captured fugitives. Two prominent instances in which abolitionists set free captured fugitives include John McHenry in Syracuse, New York, in 1851, and Shadrach Minkins in Boston of the same year.

Wilmot Proviso

The Wilmot Proviso would have banned slavery in any territory acquired from the Mexican War.

Learning Objectives

Evaluate the reasons the Wilmot Proviso failed to become law

Key Takeaways

Key Points

  • The Wilmot Proviso was a law proposed by Congressman David Wilmot to ban slavery in territories to be acquired following the Mexican War.
  • The Proviso sparked a sectarian debate in Congress that forced political leaders to make numerous compromises to determine the slave issue in newly acquired U.S. territories.
  • Southerners argued that the federal government had no constitutional grounds to legislate against the expansion of slavery.
  • Northerners claimed that the ban on the expansion of slavery was necessary in order to protect the interests of yeoman farmers and to prevent Southern agriculture from dominating the U.S. agrarian economy.

Key Terms

  • Wilmot Proviso: A controversial law, proposed by Congressman David Wilmot, that would have banned slavery in any territory to be acquired from Mexico in the Mexican War, including the area later known as the "Mexican Cession," but which some proponents construed to also include the disputed lands in South Texas and New Mexico, east of the Rio Grande.
  • state sovereignty: In American political discourse, the rights held by individual states as opposed to those held by the federal government as determined by the U.S. Constitution.

The Wilmot Proviso, as proposed by Congressman David Wilmot, would have banned slavery in any territory to be acquired from the Mexican War. The result was a violent sectarian debate in Congress that forced political leaders to make numerous compromises to determine the slave issue in the newly acquired U.S. territories.


"Whig Harmony": A cartoon depicting the ideological split within the Whig Party in the lead up to the June 1848 convention; the Wilmot Proviso was the ultimate obstacle to presidential hopeful Zachary Taylor as he attempted to court Southern support for his campaign.

Background and Context

After the capture of New Mexico and California in the first phases of the Mexican War, political focus shifted to how these new territories would be divided between slave and free states. The Wilmot Proviso, proposed in August 1846, rapidly brought the issue to the political forefront. David Wilmot, a Pennsylvanian Democrat, drafted legislation that decreed, "neither slavery nor involuntary servitude shall ever exist" in any of the new territory acquired from Mexico, including Texas and California. For many Southerners, the Wilmot Proviso forced the issue of slavery as a central component of the Mexican War. Led by John C. Calhoun, Southern slaveholders claimed that the federal government had no right to curtail the spread of slavery into any new territories, claiming that it was each individual state’s right under the principle of state sovereignty to determine whether or not its territory would be free or permit slavery.

In the North, many abolitionists and radical antislavery proponents embraced the Wilmot Proviso. Furthermore, the Wilmot Proviso found support among those who were apathetic on the slave issue, such as David Wilmot himself. For Wilmot and other Whigs, slavery was a fundamental threat to the United States not because of its brutality or coercive structure, but because it encroached on the rights of white freemen to labor and cultivate new lands in the West. In other words, for most Northern politicians, the concern was to protect free yeoman farmers’ access to land and socioeconomic opportunities in the West from the slave states of the South that sought complete domination and infiltration of any new territory in order to perpetuate plantation agriculture.

The Wilmot Proviso was killed in the Senate, but the debate it sparked revealed a fundamental divide between Northern and Southern politicians, which translated to a national sectarian split over the governance of new territories. Increasingly, both sides came to see each other as threats to national progress and prosperity.


Portrait of David Wilmot: Congressman David Wilmot proposed the Wilmot Proviso in 1846.

The Compromise of 1850

The Compromise of 1850 left the question of slave versus free states to popular sovereignty.

Learning Objectives

Evaluate the impact of the Compromise of 1850 on the slavery debate

Key Takeaways

Key Points

  • As Californian settlers applied for annexation, they drafted a proposal to be admitted to the Union as a free state, which would tip the balance of power in the Senate.
  • Southern politicians, alarmed that they would lose their grip on federal power, argued that the federal government had no right to interfere in the rights of slave owners and threatened secession if Congress admitted California as a free state.
  • This prompted a series of measures designed to appease both Northern and Southern congressmen and to establish a more equitable balance of power between slave and free states.
  • These measures, although they solved the dispute regarding California's status as a free or slave state, did not provide any long-term, guiding principles for future decisions on the sectional balance of new territories.

Key Terms

  • Compromise of 1850: A package of five bills, passed in September 1850, which defused a four-year confrontation between the slave states of the South and the free states of the North regarding the status of territories acquired during the Mexican-American War (1846–1848).
  • popular sovereignty: The principle that the authority of a state and its government is derived from the majority consent of its people and their elected representatives.
  • Henry Clay: Henry Clay, Sr. (April 12, 1777–June 29, 1852), was a lawyer, politician, and skilled orator who represented Kentucky in both the Senate and the House of Representatives.

California As a Free or Slave State

In the immediate aftermath of the Mexican War and in the midst of the California Gold Rush, a major political confrontation occurred in Congress that required many compromises in order to prevent Southern secession.

As part of their application for annexation, California settlers proposed that their state would ban slavery. However, the admission of California as a free state would tip the balance of power in the Senate. Southern politicians, alarmed that they would lose their majority, pushed for Congress to pass legislation that would allow California to be admitted as a slave state, or to extend the Missouri Compromise line to the Pacific, effectively splitting the state in half into one free state and one slave state. Pushing the issue even further, many Southern politicians argued that the federal government had no right to interfere in the rights of slave owners to move their property within the boundaries of the nation, including free states.

This prompted a series of measures designed to appease both Northern and Southern congressmen via a more equitable balance of power. Henry Clay, the leader of the Whig Party (nicknamed the "Great Pacificator”) drafted the following five compromise measures in 1850:

  1. California becomes a free state, and Texas's boundary would remain at its present-day limits.
  2. The United States would pay Texas $10 million in compensation for the loss of New Mexico territory, which Texas had previously claimed as part of its state territory.
  3. The territories of New Mexico and Utah would be organized on the basis of popular sovereignty.
  4. The Fugitive Slave Act of 1850 would be passed into law.
  5. The slave trade would be abolished in the District of Columbia.

These measures, passed through Congress in September 1850, solved the dispute regarding California's status as free versus slave, but did not provide any long-term, fundamental principle for future decisions on the sectional balance of new territories. By allowing popular sovereignty to determine slave or free states, the Senate basically guaranteed future discord over the sectional balance of power in the coming years. During the debates over California, Northern senators argued that settlers (in any territory) could curtail or ban slavery at will, while Southerners claimed that there could be no prohibition of slavery in the territories because the land belonged to all states equally. In the Compromise of 1850, popular sovereignty was not defined as a guiding principle on the slave issue going forward. Furthermore, the bill's strengthening of the Fugitive Slave Act angered many Northerners, and even provoked violence in Northern cities. In short, the Compromise of 1850 was less an effective tool for federal management of western territories and more a precarious stalemate agreed to by the North and the South that effectively shelved the slave problem for a few more years.

Nonetheless, the Compromise of 1850 was perceived by both sides as a success insofar as it staved off a greater escalation of sectional conflict. During the debate over the Compromise, John C. Calhoun, a notable defender of the South and Southern slavery, wrote an ominous speech that anticipated secession and disunion if the Northern states did not meet Southern demands. This led some politicians to accept what otherwise would have been an unacceptable bill out of fear of raising the stakes of the conflict. Senator Daniel Webster of Massachusetts, for example, spoke in favor of the Compromise, urging Northerners to abandon radical antislavery legislation while warning the South that threats to secede would inevitably result in sectional violence. Many Northern abolitionists later denounced Webster for agreeing to the “devil's compromise”; however, many politicians were relieved to enact temporary measures to keep the peace between the states.

The map distinguishes between states, territories, and land held by other countries. It shows the following states: Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia, Florida, Ohio, Michigan, Indiana, Illinois, Wisconsin, Iowa, Missouri, Kentucky, Tennessee, Alabama, Mississippi, Arkansas, Louisiana, and Texas. It shows four territories: Minnesota Territory, covering modern-day Minnesota and portions of modern-day North Dakota and South Dakota; Unorganized territory, covering modern-day Nebraska and portions of modern-day North Dakota, South Dakota, Montana, Wyoming, Colorado, Kansas, and Oklahoma; Oregon Territory, covering modern-day Washington, Oregon, Idaho, and portions of modern-day Montana and Wyoming; and Mexican Cession, also labelled

The United States, 1849–1850: A map of the United States depicting states and territories, and land held by other countries during the time period of 1849–1850.

The Kansas-Nebraska Act

The Kansas-Nebraska Act of 1854 mandated that popular sovereignty would determine the slave or free status in the region.

Learning Objectives

Evaluate how the Kansas-Nebraska Act affected the political debate over slavery

Key Takeaways

Key Points

  • The Compromise of 1850 was tested when a mass influx of settlers arrived in Kansas and Nebraska territories to determine, through popular sovereignty, whether slavery would be permitted in each region.
  • Ballot-rigging, violence, and conflict ensued in Kansas territory, leading to a low-intensity civil war referred to as "Bleeding Kansas."
  • In 1861, Kansas was admitted to the Union as a free state in the midst of the Civil War. Nebraska was not admitted to the Union until 1867, after the Civil War.

Key Terms

  • Stephen A. Douglas: (1813–1861) An American politician from Illinois who served as a U.S. Representative, a U.S. Senator, and the Democratic Party nominee for president in the 1860 election, losing to Republican Abraham Lincoln.
  • Bleeding Kansas: A series of violent political confrontations involving antislavery Free-Staters and proslavery "Border Ruffian" elements that took place in the Kansas Territory and the neighboring towns of Missouri between 1854 and 1861; also known as "Bloody Kansas" or the "Border War."
  • Kansas-Nebraska Act: A bill passed in 1854 that created the territories of Kansas and Nebraska, opened new lands for settlement, and had the effect of repealing the Missouri Compromise of 1820 by allowing settlers in those territories to determine through popular sovereignty whether they would allow slavery within each territory.

Kansas–Nebraska Act

The allure of rich farmlands and the potential for infrastructure development in the Kansas-Nebraska territories put the Compromise of 1850 to the test. The Missouri Compromise of 1820 had prohibited slavery in all new territories north of the 36° 30' latitude line, effectively banning slavery in the Kansas territory. The Kansas-Nebraska Act of 1854, however, drafted by Democrat Stephen A. Douglas (IL), repealed the Missouri Compromise of 1820 and mandated that popular sovereignty would determine any new territory's slave or free status.

The initial purpose of the Kansas-Nebraska Act was to facilitate the growth of farmland throughout the territory and the development of a transcontinental railroad through the Midwest. Douglas and other representatives hoped that by tagging on the popular sovereignty mandate, they could avoid confronting the slave issue in the organization of the Kansas-Nebraska territory. However, the act spurred a mass influx of slave owners and independent farmers into Kansas—and both groups went with the explicit aim of voting for or against slavery in the territory. The result was violence, leading to the events of a conflict known as "Bleeding Kansas."

"Bleeding Kansas"

“Bleeding Kansas” is the term used to refer to the political violence that erupted in Kansas territory and neighboring Missouri towns between proslavery and abolitionist forces. It is considered by many historians to be a precursor to the U.S. Civil War. Kansas territory was neighbors with slave state Missouri and free state Iowa. As activist settlers poured into Kansas territory with the intent of voting for or against slavery as a state-sanctioned institution, politics began to resemble a war rather than democratic balloting. Proslavery settlers came to Kansas mainly from neighboring Missouri, and some residents of Missouri crossed into Kansas solely for the purpose of voting in territorial elections. During the 1855 elections for territory legislature, thousands of “Border Ruffians” from Missouri entered the territory and rigged the ballots, creating a fraudulent majority for proslavery candidates. In response to the "Border Ruffians," antislavery settlers held a separate convention to elect their own candidates to the legislature. Proslavery groups, in turn, attacked the city of Lawrence, and John Brown, a radical abolitionist, led attacks on proslavery settlers nearby. Hostilities between the factions reached a state of low-intensity civil war, damaging Franklin Pierce's administration as the nascent Republican Party sought to capitalize on the scandal of "Bleeding Kansas" in the upcoming election.


Though the situation in Kansas territory was descending quickly into anarchy, Congress was too preoccupied with its own internal conflicts to effectively intervene. On May 22, 1856, as Senator Charles Sumner (MA) gave a speech on the violent situation in Kansas, likening the proslavery invasion of the territory to the “rape of a virgin,” Senator Preston Smith Brooks (SC) physically attacked Sumner with his cane. News of the incident shocked the nation and served to further polarize proslavery and antislavery factions. To many Northerners, Sumner was considered an antislavery martyr for standing up for his convictions. To many Southerners, however, the incident provided another example of how abolitionists were willing to use Congress as a forum to attack Southern honor, culture, and economic practices.

Southern Democrats were pleased that the Kansas-Nebraska Act repealed the Missouri Compromise, while Northerners (including Northern Democrats ) decried the opening of territory to slave owners where slavery had previously been prohibited for more than 30 years. Already a fractured party, the Whigs collapsed and made way for the Northern-dominated Republican Party: a coalition of Free-Soilers, Northern Democrats, and antislavery forces that bitterly resented the repeal of the Missouri Compromise. This, in turn, gave rise to the Know-Nothing Party, a political movement composed of ex-Whigs looking for a vehicle to fight the dominant Democratic Party. In 1854, former congressman Abraham Lincoln publicly aired his moral, legal, and economic arguments against the expansion of slavery, as well as his opposition to the Kansas-Nebraska Act in three separate speeches in Illinois.


"Forcing Slavery Down the Throat of a Free-Soiler": An 1854 cartoon depicts a giant Free-Soiler being held down by James Buchanan and Lewis Cass, who stand on the Democratic platform marked "Kansas," "Cuba," and "Central America" (referring to accusations that Southerners wanted to annex areas in Latin America to expand slavery). Franklin Pierce also grips the giant's beard as Stephen A. Douglas shoves a black man down his throat.

However, with the support of President Pierce, Douglas pushed the act through Congress, albeit with rigidly delineated sectional votes. For many Northern politicians, the Kansas-Nebraska Act was the latest in a string of proslavery laws that revealed the South's aim to aggressively expanded slavery into every state in the Union.

In 1861, Kansas was admitted to the Union as a free state in the midst of the Civil War. Nebraska was not admitted to the Union until 1867, after the Civil War.

The Ostend Manifesto and Cuba

The 1854 Ostend Manifesto justified the right of the United States to annex Cuba and implicitly justified war if Spain refused to sell the island.

Learning Objectives

Explain what the Ostend Manifesto was and why Southern expansionists supported the policy

Key Takeaways

Key Points

  • Written by Pierre Soulé (U.S. minister to Spain) and James Buchanan (U.S. minister to Great Britain), the Ostend Manifesto claimed that the threat of a possible Haiti -type slave revolt in Cuba meant that the United States would be "justified in wresting" Cuba from Spain.
  • Annexation of Cuba was a policy aggressively pursued by Southern expansionists in the wake of California's admission to the Union as a free state, but Northerners decried the document as an attempt to unconstitutionally spread slavery to other territories.
  • The political backlash against the Ostend Manifesto and the Franklin Pierce administration effectively terminated any discussions of Cuban annexation until after the American Civil War.

Key Terms

  • Ostend Manifesto: A document written in 1854 that described the rationale for the United States to purchase Cuba from Spain while implying that the United States should declare war if Spain refused.
  • Pierre Soulé: (August 31, 1801–March 26, 1870) A U.S. politician and diplomat from Louisiana best known for his role in creating the Ostend Manifesto, which was written in 1854 as part of an attempt to annex Cuba to the United States. The Manifesto was denounced, especially by antislavery elements, and Soulé himself came under severe attack.

Background and Context

Located 90 miles off the coast of Florida, Cuba had been considered a target for annexation by several presidential administrations. President John Quincy Adams described Cuba and Puerto Rico as, “natural appendages to the North American continent,” and Cuba's annexation as, “indispensable to the continuance and integrity of the Union itself.” The Spanish empire had been in gradual decline, but so long as control of Cuba did not pass to a stronger power such as Britain or France, most presidential administrations did not aggressively seek annexation.

As the sectional debate over expansion intensified, however, Southern Democrats began to look to Cuba as another potential slave state. Slavery was a centuries-old institution in Cuba, and its sugar plantation system, overall agrarian economy, and location predisposed it to the agricultural interests of the South. Hence it was believed that the annexation of Cuba might greatly strengthen the position of Southern slaveholders against industrial Northern interests. The movement for annexation grew even more intense as free states from the Western territories were admitted to the Union and political conflict erupted in the wake of the Kansas-Nebraska Act, upsetting the already delicate balance of power between slave and free states in the Senate.

Ostend Manifesto

At the suggestion of Secretary of State William L. Marcy, U.S. Minister to Spain Pierre Soulé met with U.S. Minister to Great Britain James Buchanan and U.S. Minister to France John Y. Mason at Ostend, Belgium, to discuss the Cuba matter. The resulting dispatch, drafted at Aix-la-Chapelle in October 1854, outlined the reasons the U.S. purchase of Cuba would be beneficial to all parties involved and declared that the United States would be "justified in wresting" the island from Spanish hands if Spain refused to sell. Prominent among the reasons for annexation outlined in the Ostend Manifesto were fears of a possible slave revolt in Cuba, the likes of which had already occurred in Haiti, in the absence of U.S. intervention. Racial fears raised tension and anxiety over a potential black uprising on the island that could "spread like wildfire" to the United States.

To Marcy's chagrin, the flamboyant Soulé made no secret of the diplomatic meetings, causing unwanted publicity in both Europe and the United States. In the increasingly volatile political climate of 1854, the Franklin Pierce administration feared the political repercussions of making the negotiations known, but pressure from journalists and politicians alike to publish what was agreed to in Ostend continued to mount. As a result, the dispatch was published in full at the behest of the House of Representatives. Dubbed the Ostend Manifesto, it was immediately denounced in both Northern U.S. states and Europe. It became a rallying cry for Northerners in the events that would later be termed "Bleeding Kansas," and the political fallout was a significant setback for the Pierce Administration.


When the document was published, it outraged Northerners, who viewed it as an aggressive Southern attempt to extend slavery. American Free-Soilers, recently angered by the Fugitive Slave Law (passed as part of the Compromise of 1850), decried the Manifesto, dubbed by Horace Greeley of the New York Tribune as “The Manifesto of the Brigands”, unconstitutional. The Pierce administration was irreparably damaged by the incident, and Northern Democrats began to withdraw their support and gravitate toward the nascent Republican Party.


Cartoon of the Ostend Doctrine: A political cartoon depicts James Buchanan surrounded by hoodlums using quotations from the Ostend Manifesto to justify robbing him.

Internationally, the Ostend Manifesto was seen as a threat not only to Spain, but also to all imperial powers across Europe. It was quickly denounced in Madrid, London, and Paris. To preserve what favorable relations the administration had left, Soulé was ordered to cease discussion of Cuba, and he promptly resigned. The backlash from the Ostend Manifesto shelved any expansionist plans for Cuba for several decades. The “Cuban Question” would not dominate U.S. foreign policy discussions until 30 years after the Civil War.


Portrait of Pierre Soulé: Pierre Soulé, the driving force behind the Ostend Manifesto and its resultant political fallout.

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