The Scarlet Letter (1850), is considered his magnum opus. Set in 17th-century Puritan Boston, it tells the story of Hester Prynne, a woman who gives birth after committing adultery and struggles to create a new life of repentance and dignity. Throughout the novel, Hawthorne explores themes of legalism, sin, and guilt. The book's immediate and lasting success are due to the way it addresses spiritual and moral issues from a uniquely American standpoint. It remains relevant for its philosophical and psychological depth, and continues to be read as a classic tale on a universal theme.