In 1846 Dred Scott and his wife, Harriet, sued for their freedom in a St. Louis city court. The couple had been held illegally in a free territory and then returned to a slave state. However, the lawsuit became an 11-year legal struggle that culminated in one of the most notorious decisions ever issued by the United States Supreme Court.

Supreme Court Chief Justice Roger B. Taney not only denied the Scotts their freedom, but also asserted that no person of African ancestry—free or slave—was considered a citizen and therefore was unprotected by the Constitution. The backlash against this decision was one of the factors that led to the Civil War.