Eli Whitney patented the cotton gin

On March 14, 1794, Eli Whitney received a U.S. patent for the cotton gin, a device that mechanically separates cotton fiber from its sticky seeds. The task had been so slow by hand that short-staple cotton, the type that grew across the American South, was barely worth planting.

Whitney’s machine changed the arithmetic overnight. A single gin could clean up to fifty pounds of cotton a day, work that had taken many enslaved laborers far longer. Cotton became enormously profitable—and that profitability had a brutal consequence.

Whitney’s invention revolutionized cotton production and created a vast new market for enslaved labor.

As plantations expanded to grow more cotton, the demand for enslaved workers rose with it, entrenching slavery just as some had expected it to fade. Whitney himself profited little: the gin was so simple to copy that his patent, granted in 1794, proved nearly impossible to enforce and was not effectively validated until 1807.