Online College Courses for Credit

Slavery in the United States in the 19th Century
A Nation Divided: 1800 - 1877
of 0 possible points
Slavery in the United States in the 19th Century

Slavery in the United States in the 19th Century

Author: Sophia Tutorial

Recognize the position of and thoughts about slavery as it grew in the early 19th century.

See More

what's covered
By the mid-19th century, the United States was divided into two distinct sections. The development of internal improvements and manufacturing contributed to the emergence of a northern economy centered on the principles of free labor. Meanwhile, the expansion of slavery and cotton cultivation in the Deep South contributed to the rise of an elite group of slaveholders and merchants, who justified their position through planter paternalism.

Slavery had gradually become extinct in the North during the 19th century. However, racism in both sections — North and South — helped sustain southern slavery by perpetuating principles associated with white supremacy and the perceived inferiority of African Americans. Racism within American society, along with the economic influence of cotton production, went on to affect national politics associated with slavery.

Our discussion of slavery in 19th-century America breaks down as follows:

  1. The Peculiar Institution
  2. Racism in 19th-Century America
  3. The Politics of Slavery

1. The Peculiar Institution

Although racial slavery was well-established in the United States by the early 19th century, certain trends contributed to the emergence of slavery as a “peculiar institution,” one unique to the South.

term to know
Peculiar Institution
The idea that racial slavery was an institution unique to the American South by the 19th century.

One key reason for the emergence of slavery as a “peculiar institution” in the South was the gradual end of slavery in the North beginning in the late 18th century. Antislavery activists in the North were influenced by the rhetoric and ideology associated with natural equality during the American Revolution, and by religious beliefs that increasingly viewed slavery as sinful. Moreover, the northern economy (which did not rely as heavily on slave labor), along with the development of free labor ideology, which viewed slavery as unfair competition that distorted market relationships, created less incentive to protect the institution.

One way slaves could gain freedom was through manumission.

term to know
The freeing of a slave by his or her owner.

Manumissions often occurred following the death of a slaveowner, who provided for the freedom of his slaves in a will.


Phillis Wheatley (her African name is lost to posterity) was born in Africa in 1753. In 1761, she was sold as a slave to the Wheatley family, who lived in Boston, Massachusetts. At a time when most slaves were unable to learn to read and write, Wheatley achieved full literacy and became a well-known poet. Phillis was manumitted upon the death of her master in the 1770s.

Portrait of Phillis Wheatley from her book Poems of Various Subjects (1773).

However, manumissions were quite rare and few slaveholders were willing to free their own slaves. Fewer than 80 slaveholders in New York City voluntarily manumitted slaves between 1783 and 1800.

Slaves could also gain their freedom through a process known as gradual emancipation, which became the preferred strategy for many northern state legislatures following the American Revolution.

term to know
Gradual Emancipation
Provided for the eventual freedom of slaves upon reaching certain requirements such as age or time served.

Gradual emancipation promoted the freedom of African-American slaves, but it did so in a way that satisfied the economic interests of northern slaveholders. For instance, gradual emancipation laws could promise to liberate only children born of enslaved mothers. Such laws could also require children to remain in a state of indentured servitude to their mother’s master for a certain number of years. Both requirements allowed slaveholders to continue to exploit the labor of African Americans for a time, and they caused northern emancipation to proceed at a snail’s pace.


In 1780, Pennsylvania implemented a gradual emancipation plan that required children of enslaved mothers to serve indentures of 28 years to their mothers’ masters.

Despite the slowness of gradual emancipation, and the limited number of private manumissions, the population of free blacks in the northern United States did increase significantly during the early 19th century.

did you know
By the early 19th century, every northern state had provided for the end of slavery. By 1810, the free black population in the North amounted to well over 100,000 people.

A number of Americans also expressed optimism that slavery would gradually go away throughout the entire United States once the nation stopped participating in the international slave trade. According to the U.S. Constitution, Congress could abolish American participation in the international slave trade in 1808. In 1807, Congress did just this, implementing a ban on American participation in the international slave trade effective January 1, 1808.

However, the ban on American participation in the international slave trade did not lead to the gradual death of slavery. While smuggling continued to occur after Congress enacted the ban, high fertility rates among slave women and low mortality rates relative to other regions of the world led to a natural population increase among African-American slaves in the South.


Estimates suggest that the slave population quadrupled between 1808 and 1860, from roughly one million to four million.

This natural population increase — combined with the expansion of cotton cultivation in the South — helps explain why slavery did not go away, despite gradual emancipation in the North and a ban on participating in the international slave trade.

2. Racism in 19th-Century America

Racism was another reason why slavery did not become extinct in 19th-century America. For instance, Thomas Jefferson's views on race were not unusual in his time. Jefferson doubted the intellectual capacities of African Americans and deemed them all inferior because of their skin color. He went on to suggest that such differences in skin color played a greater role in determining African Americans’ intellectual capacities than their position in forced servitude:

Thomas Jefferson

"Many millions of them [blacks] have been brought to, and born in America. Most of them indeed have been confined to tillage, to their own homes, and their own society: yet many have been so situated, that they might have availed themselves of the conversation of their masters; many have been brought up to the handicraft arts, and from that circumstance have always been associated with the whites. Some have been liberally educated, and all have lived in countries where the arts and sciences are cultivated to a considerable degree, and have had before their eyes samples of the best works from abroad….[N]ever yet could I find that a black had uttered a thought above the level of plain narration; never see even an elementary trait of painting or sculpture. In music they are more generally gifted than the whites with accurate ears for tune and time . . . . Whether they will be equal to the composition of a more extensive run of melody, or of complicated harmony, is yet to be proved. Misery is often the parent of the most affecting touches in poetry. Among the blacks is misery enough, God knows, but no poetry."
think about it
Refer the last line in the above selection: “Among the blacks is misery enough, God knows, but no poetry.” What do you think Jefferson meant by this phrase? How might have Phillis Wheatley responded to Jefferson’s claims?

Jefferson’s ideas toward race were informed by the Enlightenment, the intellectual and cultural movement of the 18th century that emphasized reason, scientific inquiry, and progress over superstition and blind faith. Beginning in the early 19th century, a number of American scientists built upon these principles by gathering data and developing theories to explain all facets of life, including racial differences and the perceived superiority of white Americans.

Starting in the 1820s, a number of American scientists accepted the idea that humans were not part of a single creation event (also known as monogenesis). Rather, to explain the variety of cultural and physical differences between people, they sought evidence to support a theory known as polygenesis.

term to know
The idea that humans experienced multiple creation events, which explained the cultural and physical differences between them.

Among the most popular methods was measuring skull capacity. Dr. Samuel George Morton and his associates robbed Indian graves for the sole purpose of collecting and measuring skulls. Morton’s most famous book, Crania Americana (1839), featured numerous images of skulls, as well as his conclusions on race based on cranial measurements.

He characterized white Americans (and Europeans) by writing:

Dr. Samuel George Morton, Crania Americana

“The Caucasian Race is characterized by a naturally fair skin, susceptible of every tint; hair fine, long and curling, and of various colors. The skull is large and oval, and its anterior portion full and elevated. The face is small in proportion to the head, of an oval form, with well-proportioned features. The nasal bones are arched, the chin full, and the teeth vertical. This race is distinguished for the facility with which it attains the highest intellectual endowments.”

In contrast, he described individuals of African descent by writing:

“Characterized by a black complexion, and black, woolly hair; the eyes are large and prominent, the nose broad and flat, the lips thick, and the mouth wide; the head is long and narrow, the forehead low, the cheekbones prominent, the jaws protruding, and the chin small. In disposition the Negro is joyous, flexible, and indolent; while the many nations which compose this race present a singular diversity of intellectual character, of which the far extreme is the lowest grade of humanity.”
Compare Morton’s conclusions with Thomas Jefferson’s portrayal of African Americans. In what ways were they similar? In what ways were they different?

By the 1850s, Morton’s conclusions were widely accepted. A number of scientists in the northern and southern United States, including Louis Agassiz, who taught zoology and geology at Harvard University, and Josiah Nott, who was a surgeon and physician from Alabama, continued to popularize polygenism.

This 1857 illustration from a book, titled Indigenous Races of the Earth, indicates that the “Negro” occupied a place between the Greeks and chimpanzees and makes this distinction based on a skull diagram.

think about it
Apply the lens of race to the above image. How might this lens reveal the motives and methods of those who advocated polygenesis?
big idea
Similar to Thomas Jefferson and the Enlightenment thinkers before them, Morton and the advocates of polygenesis approached their experiments already assuming that whites were superior to any other race. Their methods, measurements, and conclusions simply reflected this assumption, but the consequences were profound. The theory of polygenism codified racism in the United States by giving the notion of black inferiority the lofty mantle of science. Morton and other scientists argued that African Americans were biologically inferior to whites and concluded that African Americans could never be equal to whites and could never achieve progress.

3. The Politics of Slavery

Racism was certainly a key factor in the perpetuation and defense of slavery in the United States. Still, southern slaveholders worked continuously to ensure that their “peculiar institution” remained protected by the federal government. The expansion of democracy during the 1820s and 1830s was particularly crucial. Southern lawmakers, such as John C. Calhoun, grew increasingly concerned about a democratic phenomenon known as the tyranny of the majority.

term to know
Tyranny of the Majority
A political phenomenon in which the interests of a group in the majority overwhelmed or ignored the interests and concerns of minority groups.

Calhoun and other white southerners watched with concern as the North’s slave population declined, while its free, white voting population continued to increase at the expense of the South. They worried that if political power in Congress went to a northern majority that became hostile to slavery, the South’s economy and culture would be in danger. For this reason, white southerners in Congress bristled at what they perceived to be northern attempts to deprive them of their livelihood.

Recall that John C. Calhoun opposed John Quincy Adams’s Tariff of 1828, because he believed it would disproportionately harm the South, which relied heavily on imports, and benefit the North, which would receive protections for its manufacturing centers. More importantly, Calhoun was worried that the tariff would open the door for other federal initiatives that might harm slavery. It was for these reasons that Calhoun argued for nullification in his “South Carolina Exposition and Protest” (Calhoun, 1992):

John C. Calhoun, "South Carolina Exposition and Protest"

“If it be conceded, as it must be by every one who is the least conversant with our institutions, that the sovereign powers delegated are divided between the General [Federal] and State Governments, and that the latter hold their portion by the same tenure as the former, it would seem impossible to deny to the States the right of deciding on the infractions of their powers, and the proper remedy to be applied for their correction. The right of judging, in such cases, is an essential attribute of sovereignty. . . .”
term to know
The theory that a state could nullify, or declare a federal law null and void, if it threatened the interests or sovereignty of that state.

John C. Calhoun, shown here in a ca. 1845 portrait by George Alexander Healy.

Calhoun’s support of nullification illustrated the growing importance of states’ rights arguments to the southern states by the mid-19th century. Calhoun increasingly saw white southerners as an embattled minority and, in an attempt to preserve both the Union and the South’s economic and political interests (which revolved around slavery), Calhoun advanced the idea of a concurrent majority.

term to know
Concurrent Majority
A majority of a separate region (that would otherwise be in the minority of the nation) with the power to veto or disallow legislation put forward by a hostile majority.
did you know
Calhoun defended the South on these grounds, despite the fact that eight of the first 12 presidents of the United States had been southern slaveholders.

Calhoun’s idea of the concurrent majority found full expression in his essay “A Disquisition on Government” (Calhoun, 1992), which was published after his death in 1850:

John C. Calhoun, "A Disquisition on Government"

“There are two different modes in which the sense of the [political] community may be taken; one, simply by the right of suffrage, unaided; the other by the right through a proper organism. Each collects the sense of the majority. But one regards numbers only….The other, on the contrary, regards interests as well as numbers….The former of these I shall call the numerical, or absolute majority; and the latter, the concurrent, or constitutional majority. I call it the constitutional majority, because it is an essential element in every constitutional government….”
think about it
Why do you think Calhoun referred to the concurrent majority as the “constitutional majority?”

Calhoun went on to argue that the interests of any numerical majority could be countered by constitutional measures that protected minority interests, including those of southern slaveholders (Calhoun, 1992):

“The necessary consequence of taking the sense of the community by the concurrent majority give to each interest or portion of the community a negative on the others. It is this mutual negative among its various conflicting interests, which invests each with the power of protecting itself — and places the rights and safety of each, where only they can be securely placed, under its own guardianship. Without this there can be no systematic, peaceful, or effective resistance to the natural tendency of each to come into conflict with the others; and without this there can be no constitution.”

think about it
Which Americans would most likely support Calhoun’s idea of a “mutual negative” among the “various conflicting interests” in the United States? Which Americans would most likely oppose Calhoun’s idea? Why?
big idea
Calhoun’s “Disquisition on Government” illustrated his suspicion toward democratic majorities, and their potential ability to implement legislation that could challenge southern interests. If a majority became hostile toward the interests of a minority group, Calhoun argued that the minority had the constitutional authority to take action through a variety of means, including nullification. Perhaps most interesting about the above passages was that Calhoun did not go so far as to suggest that the minority interest could separate from the political community if it was infringed upon by the majority.
Although slavery gradually disappeared in the North and a small white elite owned the majority of African-American slaves in the South, slavery remained entrenched within the United States by the 19th century for a number of reasons. The domestic slave trade allowed the African-American slave population to continue to grow and expand in the South, even though northern states implemented gradual emancipation laws and Congress outlawed American participation in the international slave trade. Likewise, profoundly racist ideas that ultimately underlay the theory of polygenism reinforced white supremacy throughout the United States. Finally, political defenses of slavery became prevalent by the mid-19th century, especially Calhoun’s argument that the South’s “concurrent majority” could nullify or overrule any federal legislation deemed hostile to its interests.

This tutorial curated and/or authored by Matthew Pearce, Ph.D

Source: Race/Skulls image, PD, Morton, S.G. (1839). Crania Americana. (pp. 5-7) Ret from, Jefferson, T. (1853) Notes on the State of Virginia. Ret from, John C. Calhoun, Union and Liberty: The Political Philosophy of John C. Calhoun, ed. Ross M. Lence (Indianapolis: Liberty Fund, 1992). Ret 1/31/2017 from the Web:, Openstax tutorials 11.2 and 12.2 Some sections edited for brevity. Image of Phillis Wheatley, PD .Image of John Calhoun, PD

Terms to Know
Concurrent Majority

A majority of a separate region (that would otherwise be in the minority of the nation) with the power to veto or disallow legislation put forward by a hostile majority

Gradual Emancipation

Provided for the eventual freedom of slaves upon reaching certain requirements such as age or time served


The freeing of a slave by his or her owner

Peculiar Institution

The idea that racial slavery was an institution unique to the American South by the nineteenth century


The idea that humans experienced multiple creation events, which explained the cultural and physical differences between them

Tyranny of the Majority

A political phenomenon in which the interests of a group in the majority overwhelmed or ignored the interests and concerns of minority groups

People to Know
John Calhoun

Southern lawmaker and politician from South Carolina who sought to defend the South’s regional interests and formulate a philosophy of states’ rights in the early to mid-nineteenth century. His “South Carolina Exposition and Protest” in 1828 and “A Disquisition on Government” in 1850 articulated theories of nullification and the concurrent majority.

Nat Turner

A black slave in Southampton County, Virginia, who led the most significant slave rebellion in American history, resulting in the deaths of scores of whites before the rebellion was suppressed.

Phillis Wheatley

Born in Africa in 1753, Wheatley was sold as a slave to the Wheatley family in Boston, Massachusetts in 1761. She achieved full literacy and became a well-known pre-nineteenth century poet.