Before she became a literary legend, she wanted to be a cartoonist.Flannery O’Connor was among the greatest American writers of the second half of the 20th century; she was a writer in the Southern tradition of Eudora Welty, William Faulkner, and Carson McCullers, who wrote such classic novels and short stories as Wise Blood, The Violent Bear It Away, and “A Good Man is Hard to Find.” She is perhaps as well known for her tantalizing brand of Southern Gothic humor as she is for her Catholicism. That these tendencies should be so happily married in her fiction is no longer a surprise. The real surprise is learning that this much beloved icon of American literature did not set out to be a fiction writer, but a cartoonist. This seems to be the last well-kept secret of her creative life. Flannery O’Connor: The Cartoons, the first book devoted to the author’s work in the visual arts, emphasizes O’Connor’s most prolific period as a cartoonist, drawing for her high school and...