My life has been incredible, Katherine Anne Porter used to say, "I don't believe a word of it." Author of the best-selling novel, "Ship of Fools," winner of the Pulitzer Prize and the National Book Award for her short stories, Porter was both the first lady of American letters and a woman whose indomitable will forged a life that, as biographer Joan Givner makes clear, was not only incredible but may have been her most creative fiction of all.

Born Callie Porter in the log-cabin poverty of rural Texas, she, like Jay Gatsby, invented her own history, changing her name and "acquiring" a...