In 1843, the Louisiana Supreme Court heard the case of a slave named Sally Miller, who claimed to have been born a free white person in Germany. Sally, a very light-skinned slave girl working in a New Orleans caf, might not have known she had a case were it not for a woman who recognized her as Salom Muller, with whom she had emigrated from Germany over twenty years earlier. Sally decided to sue for her freedom, and was ultimately freed, despite...