In 1834, Dred Scott, a slave, had been taken to Illinois, a free state, and then Wisconsin territory, where the Missouri Compromise of 1820 prohibited slavery. Scott lived in Wisconsin with his master, Dr. John Emerson, for several years before returning to Missouri, a slave state. In 1846, after Emerson died, Scott sued his master’s widow for his freedom on the grounds that he had lived as a resident of a free state and territory.
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