The cotton gin was an invention by Eli Whitney, a Northerner, that increased the production of cotton by mechanically removing the seeds. Before his invention, the process of removing seeds was extremely labor intensive, and a large number of slaves was required to produce a relatively small amount of cotton. With this invention, a single slave could produce as much cotton as The cotton gin increased production of cotton exponentially, and slave owners took advantage of this by purchasing more slaves, thus increasing the eventual profit margin. The introduction of the cotton gin provided the Southern slave owners with the chance to increase their profit by an untold amount. Due to the increased productivity the gin offered, less slaves could produce the same amount of cotton. The Southern slave owners decided that the best use of the cotton gin would be to purchase more slaves, and effectively raise cotton production to previously unreached levels.
The cotton gin allowed a "Cotton Kingdom" to form in the South. Many plantation owners increased their personal wealth, and the amount of cotton exported increased by thousands of tons. Cotton became the number one export of the United States. In line with this increase of production, was the increase in the number of slaves. Despite a ban on the international slave trade, internal trade was still legal and the number of slaves in America continued to rise annually.