Manifest Destiny and Expansion: 1815–1887

King Cotton

Eli Whitney's Cotton Gin

Eli Whitney's invention of the cotton gin in 1793 made it possible to process massive amounts of cotton in a relatively short period of time, helping to make cotton king of the cash crops.

A native of Massachusetts, Eli Whitney had no idea the enormous impact he would make on America's history when he took a job in the South in the late 18th century. In his youth he showed an instinctive grasp of mechanisms. He attended Yale University, where he studied science and technology, or "the applied arts," as technology was called at the time. Upon graduation, unable to find a job in technology, he turned to teaching and secured a position in the South. However, upon arrival, he discovered the quoted salary had been halved. Consequently, he ended up in Georgia, assisting a plantation manager. It was there Whitney spotted the need for a machine that cleaned the seeds from the short fibers of upland cotton bolls.

Prior to his invention of such a machine, enslaved workers cleaned the seed from cotton bolls by hand. A cotton boll is the fluffy round clump of fiber that grows on the cotton plant and is used in the manufacture of clothing and other products. The seeds from long-fiber cotton could be separated easily, making the fibers easy to clean before spinning into yarn. But long-fiber cotton only grew on the sandy islands off Georgia, while short-fiber upland cotton grew well throughout the mainland. However, the seed clung tightly to those short fibers, making it extremely difficult to clean. Therefore, harvesting cotton was labor-intensive and time-consuming. To solve the problem, Eli Whitney invented the cotton gin, a machine that removed seeds from the fibers of upland cotton bolls.
Eli Whitney was 28 years old when he invented the cotton gin in 1793. He later developed a method to mass-produce muskets, which helped the North win the Civil War.
Credit: Courtesy of the Library of Congress, LC-USZC4-12270

Cotton Gin

Using a cotton gin, workers could clean 10 times more cotton than cleaning by hand in the same amount of time.

Impact of Whitney's Cotton Gin on Slavery

Because the cotton gin could clean so much cotton, plantations grew, and so did the use of enslaved labor.

Whitney's cotton gin pulled raw cotton fiber through a group of wire teeth fastened on a revolving cylinder. The fiber passed through the narrow slots between the teeth, and the seeds dropped away. The cotton gin was powered by a worker, an animal, or a water wheel. As a result of its simple design, many farmers copied the machine, despite the patent Whitney registered.

The cotton gin was such a successful labor-saving device that it enabled a worker to clean 10 times more cotton than cleaning by hand. Whitney's machine mechanized work done by enslaved labor. The cotton gin, however, did not reduce the need for an enslaved workforce or end slavery. On the contrary, it spurred a huge growth in cotton planting to meet the rising international demand for cotton, and cotton plantations grew in number and size. As a result, large numbers of workers were needed to labor in the vast cotton fields. Plantation owners made the economic decision to expand slavery to meet this need. With the cotton gin and enslaved labor, the South went from producing three million pounds of cotton in 1792 to 11 million pounds in 1797. Whitney's invention ensured the system of slavery was essential to the South's pre–Civil War economy.

Cotton Is King

King Cotton dominated the South's economy, created the plantation system, and increased reliance on enslaved labor causing further entrenchment of the institution in the Southern economy.

The term King Cotton describes the fiscal and political importance of cotton in the pre–Civil War South. With the invention of the cotton gin, cotton became the cash crop of the South, replacing tobacco. It dominated the economy, shaped the politics, and greatly expanded the Southern plantation system that produced vast amounts of cotton for the United States and Europe. The invention of machines that spun and wove cotton into cloth further fueled the demand for raw cotton. Key figures in this industry included James Hargreaves, inventor of the spinning jenny in 1770; Sir Richard Arkwright, inventor of the water frame in 1769; and Edmund Cartwright, inventor of the power loom in 1785. The South's production of cotton doubled each decade in the 19th century before falling off during the Civil War. Even so, cotton would remain America's leading export well into the 1930s.

The cotton-dominated plantation system of the South relied on large, privately owned tracts of land for cultivating cash crops such as cotton and tobacco and further depended on enslaved workers to labor in the fields. During the antebellum period, the historical era in the South from approximately 1800 to the onset of the Civil War, slavery became as important to cotton as the cotton gin. As a result, slavery spread. There were six Southern slave states in 1790 and 15 in 1860 stretching across the South from the Atlantic coast into east Texas. The plantation system fostered a way of life that was dependent on enslaved labor for every aspect of daily life, from working the cotton fields to tending the needs of white planters' families in the huge mansions that planters built. King Cotton also dominated the South's local, state, and national politics and legislation. State laws included Slave Codes, laws that determined the status of enslaved persons as property. One such code, for example, made it illegal to teach a slave to read. Plantation owners feared that a slave who could read was more likely to seek freedom. Plantation owners felt they needed to retain their enslaved workers, as the cotton-based economy required a large workforce.

Cotton exports grew to exceed over half the total exports of the United States. Much of those cotton exports went to Britain, and the South believed if there were a war, Britain would stand with it. Consequently, the South was certain it would succeed should there be a war with the Union. In 1858 U.S. Senator James H. Hammon from South Carolina even declared on the Senate floor: "You dare not make war upon cotton! No power on earth dares make war upon it. Cotton is king." But Britain neither stood in alliance with the South before or during the Civil War nor intervened in any way. King Cotton, which relied so heavily on slavery, could not protect the system of slavery it had spawned.

Slave Pen, Alexandria, Virginia

Enslaved Africans constituted the workforce for picking cotton in the pre-Civil War South. By 1860 their population had reached 3.9 million men, women, and children.
Credit: Courtesy of the Library of Congress, LC-DIG-ppmsca-05453