The Dred Scott Decision was a landmark Supreme Court case in Black history that took place in 1857. Dred Scott was an enslaved African American man who had lived in both free states and territories where slavery was prohibited, before returning to a slave state with his owner.

Scott sued for his freedom on the basis that his residence in free territories should have made him a free man. The Supreme Court, however, ruled against him in a 7-2 decision. The Court held that African Americans, whether enslaved or free, could not be considered citizens of the United States and therefore had no standing to sue in federal court.

This decision not only denied Dred Scott his freedom, but it also further entrenched the institution of slavery in the United States. The ruling declared that the Missouri Compromise of 1820, which prohibited slavery in certain territories, was unconstitutional, leading to heightened tensions between the North and South and ultimately contributing to the outbreak of the Civil War. The Dred Scott Decision is often seen as one of the most infamous and consequential Supreme Court decisions in American history.