Dred Scott v. Sandford (1857) Definition

A U.S. Supreme Court decision in which the Court ruled that African Americans, whether enslaved or free, were not United States citizens and therefore did not have the right to sue in federal court. The Court also ruled that the federal government could not prohibit slavery in the territories. The decision was a prime factor leading to the Civil War, but was eventually rendered moot by the 14th Amendment to the U.S. Constitution—which provides that any person born or naturalized in the United States is a citizen of the nation and of the state where they reside.