"Dred Scott first went to trial to sue for his freedom in 1847. Ten years later, after a decade of appeals and court reversals, his case was finally brought before the United States Supreme Court. In what is perhaps the most infamous case in its history, the court decided that all people of African ancestry -- slaves as well as those who were free -- could never become citizens of the United States and therefore could not sue in federal court. The court also ruled that the federal government did not have the power to prohibit slavery in its territories. Scott, needless to say, remained a slave." - Public Broadcasting Service (PBS)