Carson McCullers was born Lula Carson Smith in Columbus, Georgia, on February 19, 1917. The Heart Is a Lonely Hunter (1940) was her first novel—published when she was only twenty-three years old—and her most autobiographical.

McCullers's father was a jeweler and a watch repairman, and her mother worked for the jeweler who had employed her father before he opened his own store. The Smiths were of moderate means but were regarded as a highly respectable family. Carson became a passionate pianist in her teenage years, but soon realized that writing was her true calling. She once said that writing was her "search for God." Certain aspects of the character Mick in The Heart Is a Lonely Hunter are drawn from McCullers's own experience as she came of age.

Critics often compare McCullers to other Southern women writers of her time—Eudora Welty, Flannery O'Connor, Katharine Anne Porter—while others believe she is more closely linked to Thomas Wolfe, Sherwood Anderson, and William Saroyan. McCullers herself said that she wrote in the tradition of the Russian realists, an inclination she attributed to her Southern heritage. Identifying herself as a Southern writer, she was interested in the so-called "gothic" quality that many critics indiscriminately applied to Southern fiction. In an article entitled "The Russian Realists and Southern Literature," McCullers reacted against overuse of the term "gothic," saying she thought the Southern fiction of her generation was, on the contrary, rooted in realism and therefore did not depend on supernatural incidents or explanations. McCullers felt that the Russian realists of the nineteenth century and the Southern realists of the twentieth century had much in common, as both groups wrote about regions that had "peasant" classes.

McCullers worked on the manuscript that eventually became The Heart is a Lonely Hunter while she was studying writing at New York University and Columbia University. In her comments prefacing the outline she sent to a publisher, McCullers makes it clear that the novel is about "five isolated, lonely people in their search for expression and spiritual integration with something greater than themselves." She explains the novel's three-part structure as a fugue (a musical composition featuring several repeating themes): Part One introduces the broad theme of "man's revolt against his own inner isolation and his urge to express himself as fully as possible" as one voice, first through John Singer and then through the other major characters. Part Two demonstrates the inevitable failure of each person, which is brought on by a combination of free will and environmental entrapment. Part Three functions as a coda; the situations of the characters ultimately end up worse than they were before Singer entered their lives.

McCullers sets off the novel's principal theme—man's struggle against isolation and his need for expression—by using five "counter-themes" (McCullers conceived her projected novel as a work of music). Each of these five counter-themes—the need for people to create a unifying deity or principle, the likelihood that any such manmade god will be an illusion, the societal suppression of individuality, the perversion of man's urge to cooperate with others, and the shining moments of heroism that occasionally characterize otherwise ordinary individuals—develops and elaborates on the principal theme.