Lesson Plan 5 | Expansion of Slavery (1787-1803)


Forced labor in the colonies began because of a shortage of labor and was comprised of mostly white indentured servants, convicts, vagabonds, and children who were sent to American colonies well into the seventeenth century.  By 1680, the flow of indentured migrants from Europe lessened, and the agricultural South’s demand for the labor shortage gave way to the expansion of African slavery. The Founding Fathers wanted to rid themselves of the evil of slavery, but it became evident that slavery had undergirded the nation’s economy, dominated its politics, and would eventually lead to civil war.

We will examine the slavery issue at the Continental Congress 1787, and how the delegates proposed an immediate ban on the importation of slaves. South Carolina and Georgia delegates threatened to withdraw from the new United States of America. Other events furthered the expansion of slavery: the invention of Eli Whitney’s cotton gin; the Fugitive Slave Law, 1793; and the development of slavery with the Louisiana Purchase in 1803.


Examine the expansion of slavery.
Northern states undertook to abolish slavery 1774 - 1804
Examine the slavery issue at Continental Congress 1787
Northwest Ordinance bans slavery
Effect of Eli Whitney’s cotton gin on slavery
The results of the Fugitive Slave Law, 1793
Expansion of Slavery with Louisiana Purchase, 1803

Time: This lesson designed for one class period.


Primary sources of information
Artists’ illustrations

Background Information:

The sparsely populated agricultural South sought to commercially expand its cash crops of tobacco, rice, and cotton.  The southern colonies were the heart of the farming labor system, and slaves helped with the growing demand for cotton from European and northern mills, which drove prices up - cotton became the nation’s most valuable commercial product in the antebellum years. The Colonies of the North practiced economic diversity with trade, commerce, banking, shipping, and manufacturing. The South refused to embrace economic diversification.  This political stage created a divided nation that would eventually find itself in a civil war.

Northern States Under Took to Abolish Slavery 1774 – 1793

From 1774 – 1804, our Founding Fathers made many attempts to ban slavery from the newly formed government. In the Declaration of Independence to the Continental Congress and beyond, these Founding Fathers took their beliefs further than words and founded antislavery societies and amended the state Constitution of Vermont to ban slavery.  In Pennsylvania, Massachusetts, New Hampshire, Connecticut, Rhode Island, New York, and New Jersey, antislavery legislation was adopted, and states freed their slaves.

All compromises and concessions made in the Declaration of Independence and the Constitution were to appease the southern colonies. The southern colonies vehemently opposed all antislavery language.  Without the South, this new fledgling America would not have prevailed.


1774: Quakers in Pennsylvania set up the first abolitionist society.

1774: Benjamin Franklin and Benjamin Rush founded America’s first anti-slavery society. John Jay, Founding Father, and Chief Justice was president of an anti-slavery society in New York.

1776: The Pennsylvania Quakers free their slaves.

1776: The Declaration of Independence declares that “All men are created equal.”

1777: Vermont amends its constitution to ban slavery. Over the next 25 years, other Northern states emancipate their slaves and ban the institution: Pennsylvania, 1780; Massachusetts and New Hampshire, 1783; Connecticut and Rhode Island, 1784; New York, 1799; and New Jersey, 1804. Some state laws stipulate gradual emancipation.

1787: The Northwest Ordinance bans slavery in the Northwest Territory (what becomes the states of Ohio, Indiana, Illinois, Michigan, and Wisconsin). The ordinance together with emancipation laws creates a free North.

The Northwest Ordinance bans slavery in the Northwest Territory

1787-1788: Drafted in 1787 and ratified in 1788, the United States Constitution does not directly mention the institution of slavery, but it addresses it indirectly in three places:

It grants Congress the authority to prohibit the importation of slaves after twenty years.
The Three-Fifths clause in Article I settles the debate over whether to count slaves for determining taxation and representation. For those purposes, all free persons in the districts, including indentured servants, are counted. To that total is added the number of “three-fifths of all other persons”- i.e., slaves.
Article IV, Section 2 required that a “person held to service or labor” in one state, who escapes to another state, "shall be delivered up on claim of the party to whom such service or labor shall be due.” Enforcement of the clause is not specified.

1793: To enforce Article IV, Section 2, the U.S. Congress enacts the Fugitive Slave Law. It allows slaveowners to cross state lines to recapture their slaves. They must then prove ownership in a court of law. In reaction, some Northern states passed personal liberty laws, granting the alleged fugitive slaves the rights to habeas corpus, jury trial, and testimony on their own behalf. These Northern state legislatures also pass anti-kidnapping laws to punish slave-catchers who kidnap free blacks, instead of fugitive slaves.

Guiding Questions:

  • How did the differences in the economies of the North and South cause the expansion in slavery?
  • Why do you think the North was so against slavery and the South thought it was a way of life?
  • Why do you think the Declaration of Independence and the Constitution were modified for the southern states?
  • What is your understanding of Article IV and do you agree with it? What party supported it?
  • What did the Northwest Ordinance guarantee about free states? 

Eli Whitney’s Cotton Gin Perpetuates Slavery:

Eli Whitney’s Cotton Gin invented in 1793, made removal of the seeds from short-staple cotton easier than removing cotton from seeds by hand.  The cotton gin consisted of a cylinder with rows of wire teeth rotating in a box that caught the cotton fibers, a second cylinder rotating in the opposite direction, pulled the cotton from the wires. A slave using the cotton gin would be able to clean fifty times what a single slave could do by hand in a day.

The cotton gin revitalized the slave industry and made possible the westward growth of slavery.  Cotton production increased with new types of cotton, and prices rose quickly, and the South became the world’s leading cotton supplier. The Industrial Revolution made textiles a massive industry. Slavery had been diminished by the strong abolitionist sentiment, and now dashed the hopes of the Founding Fathers that this institution would die out.

First Fugitive Slave Law, 1793

One year after the formation of the Democratic Party, Congress passed the first Fugitive Slave Law in 1793, by a vote of 48 – 7 with 14 abstaining. The legislation implemented Article IV of the Constitution requiring the federal government to go after runaway slaves. The law-imposed fines on anyone interfering with the slave master’s right to reclaim his slave. It also allowed slave owners to cross state lines to recapture their slaves.

Most northern states had abolished slavery and chose not to enforce the Fugitive Slave Act of 1793.  These northern states countered by passing personal liberty laws to protect free blacks from being kidnapped or mistaken as slaves and required slave owners and fugitive hunters to produce evidence that their captives were fugitive slaves.  In addition, northern state legislatures passed anti-kidnapping laws to punish slave-catchers who kidnapped free blacks, instead of fugitive slaves.

Fugitive slaves circumvented the law with the help of the Underground Railroad that provided assistance to slaves to escape to northern states or Canada. The Underground Railroad was comprised of abolitionist and freed blacks. The most famous “conductor” of the Underground Railroad was Harriet Tubman, she made nineteen trips to the South and helped some three hundred slaves escape.

The idea of the North undermining the institution of slavery angered the South. By 1850, there would be a stronger Fugitive Slave Act that would strengthen the law of 1793.

Louisiana Purchase, 1803

The United States wanted free access down the Mississippi River to the Gulf of Mexico. President Jefferson learned that Spain had ceded the territory to France. France had hoped to build an empire in North America, but an impending war with England made Napoleon abandon those plans. The prospect of war made it too expensive for France to develop this vast amount of territory. The Louisiana Purchase was acquired from France for a purchase price of $15 million which doubled the size of the United States for less than three cents an acre.

The Louisiana Territory would become part or all of fifteen states that would be created from this land deal. Major significant questions about what parts of this acquisition would be free territories or slave territories would begin.  Alexander Hamilton’s editorial dated July 5. 1803, he gives an accurate assessment of the pros and cons of the purchase as it relates to the period. https://founders.archives.gov/documents/Hamilton/01-26-02-0001-0101.

With new lands opening, cotton would be extended from the tidewater states to Mississippi and eventually to Texas. In addition to cotton, sugar cane would find Louisiana a perfect climate and tobacco moved westward as well. These changes would require more slaves to work the fields.

Guiding Questions:

  • What did the Fugitive Slave Law of 1793 require northern and southern states to do?
  • What were the consequences to the Fugitive Slave Law? What did the North do? What event was started because of this law?
  • How did the South react to the North concerning the Fugitive Slave Law of 1793?
  • How did the cotton gin help to increase the need for slavery?
  • Who demanded the cash crop of cotton? What did that do for the southern economy?
  • What other circumstances increased the need for more slaves?
  • What did the first Fugitive Slave Law of 1773 allow the slave owners to do?
  • How did the North react to the Fugitive Slave Law?
  • How do you think the Louisiana Purchase affected the expansion of slavery?
  • Read the editorial from the New York Evening Post, dated July 5, 1803, by Alexander Hamilton. What do you think Hamilton thinks about the Louisiana Purchase?


The Reader’s Companion to American History by Eric Foner & John A. Garraty (Houghton Mifflin Company) 681 – 682, 1150 – 1151,
Hamilton editorial https://founders.archives.gov/documents/Hamilton/01-26-02-0001-0101.
Extension of slavery http://www.let.rug.nl/usa/outlines/history-1994/westward-expansion-and-regional-differences/extension-of-slavery.php