Although Nathaniel Hawthorne called himself "the obscurest man in American letters," his achievements in fiction, both as short-story writer and novelist, offer models fashioned too well for contemporary and later writers to ignore. Even though fame was slow to come and his wallet remained relatively thin throughout his career as a writer, Hawthorne claimed a central place in American letters, becoming, in time, an influential force in the artistic development of such writers as Herman Melville, Henry James, William Dean Howells, Mary Jane Wilkins Freeman, Sarah Orne Jewett, William Faulkner, and Flannery O'Connor, members of the so-called Hawthorne School. His focus on the past of the nation, especially the Puritan era, his delving into the social and psychological forces underlying human behavior, his reliance on symbols to convey rich and ambivalent value to his stories and romances, his insistence on finding and understanding the sources of humanity 's darker side, and his exploration of such themes as isolation, monomania, guilt, concealment, social reform, and redemption not only created a following among aspiring writers but also brought him into the nation's classrooms, where The Scarlet Letter (1850), to name only his most famous work, still holds a firm place: more than eighty editions of it are available in formats ranging from textbooks, casebooks, and paperbacks to audio cassettes and CD-ROMs.