The Ballad of the Sad Café (1943) is generally considered one of McCullers's best works of fiction and her most successful exploration of her signature themes: loneliness and the effects of unrequited love. McCullers was twenty-four-years-old when she began writing the novella during the winter of 1941. Citing her remark that "everything significant that has happened in my fiction has also happened to me," McCullers's biographer, Virginia Spencer Carr, noted that The Ballad of the Sad Café was most likely inspired by several events in her life at this time. For example, the story's depiction of unreciprocated love is often seen as a grotesque representation of her own one-sided infatuations with the Swiss journalist and novelist Annemarie Clarac-Schwarzenbach and the American writer Katherine Anne Porter. Similarly, the motif of the romantic triangle is regarded as a distorted rendering of the situation between McCullers, her husband, and the American composer David Diamond.

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On the initial publication of The Ballad of the Sad Café, Tennessee Williams wrote that it is "assuredly among the masterpieces of our language in the form of the novella." V. S. Pritchett considered it evidence that McCullers was "the most remarkable novelist... to come out of America for a generation." William Clancy stated that the work's "metaphysical fusion of horror and compassion" represented "an achievement equaled by few other contemporary American writers." The critical reaction has not been unanimously favorable, however. Robert Drake has called The Ballad of the Sad Café "ridiculous . . . with its fabricated primitivistic folkishness." Lawrence Graver has argued that while the novella is "by far the best of Mrs. McCullers's excursions into the grotesque . . . it is not without reminders of the penumbral insistence that mars her worst work," namely the sense that "too much is made of dark nights of the soul and of things going on there that only God can understand." Nonetheless, The Ballad of the Sad Café is generally regarded as one of her best works of fiction. The 1950s, 1960s, and 1970s saw renewed interest in McCullers's body of work. During these decades numerous studies appeared on the novella that focused on issues such as the role of the narrator, the nature of love, the relationship between the text and the traditional ballad form, its mythical qualities, its connection to the Southern Gothic tradition, and its representation of sexuality and gender

http://www.enotes.com/short-story-criticism/ballad-sad-cafe-mccullers-carson