Final answer:
Dred Scott was 1) an enslaved person who sued for freedom, arguing that his residence in free states entitled him to emancipation. His case led to the Supreme Court's 1857 decision.
Step-by-step explanation:
Dred Scott was 1) an enslaved person who sued for his freedom. Born into slavery in Virginia, Scott was taken by his enslavers to the free state of Illinois and the free territory of Wisconsin, areas where slavery was prohibited.
Returning to Missouri, Scott sought to become legally free based on his extended residence in free lands. In the landmark Supreme Court case Dred Scott v.
Sandford in 1857, the Court denied his claim, stating that no person of African ancestry could claim citizenship in the U.S. and therefore could not sue in federal court, effectively ruling that the Missouri Compromise was unconstitutional.
His case had a significant impact on the country, serving to further divide the North and South over the issue of slavery. The decision underscored the lack of legal standing and rights for enslaved people and indicated that slavery could not legally be prohibited in the territories.