The novel is not autobiography, but many of Fitzgerald's personal circumstances and experiences are reflected in it.
Many of Fitzgerald's biographers, as well as Fitzgerald himself, noted that Fitzgerald lived his life with a kind of divided personality--the romantic who sought an exciting, glittering lifestyle and the Midwesterner who still believed in traditional American values. These two very different aspects of Fitzgerald are reflected in Gatsby, the romantic dreamer, and Nick Carraway, the realist and voice of Midwestern integrity.
Many of Fitzgerald's experiences are incorporated into Jay Gatsby and his former self, Jimmy Gatz. Like Jimmy, Fitzgerald as a boy rejected the circumstances of his own birth. He sometimes fantasized that he was a foundling, that he really had been born into a family very different from his own--one of wealth and social standing (even royalty). Jimmy found his father to be an embarrassment; Fitzgerald had often been embarrassed by his eccentric mother.
Also like Gatsby, Fitzgerald had served as a lieutenant in World War I and had met the woman of his dreams, Zelda Sayre, while stationed in the South. Many similarities exist between Zelda of Montgomery, Alabama, and Daisy Fay of Louisville; like Daisy, Zelda was beautiful and popular, much pursued by the young officers stationed at the nearby army camp. Fitzgerald visited Zelda at her father's fine home, just as Gatsby spent time with Daisy in her father's beautiful house.
Zelda would not marry Fitzgerald until he had money and could support her, but Fitzgerald's experience with poor boys pursuing rich girls, a major element in the novel as Gatsby longs for Daisy, involved Fitzgerald's relationship while in college with another young woman, Ginevra King. She was from an enormously wealthy family in Chicago, and Fitzgerald's own family and lack of wealth made him unacceptable as a suitor. Fitzgerald biographers have written of an incident that occurred when Fitzgerald went to visit Ginevra at her family home and was treated coldly by her family: "Poor boys shouldn't think of marrying rich girls," he reportedly was told, and their relationship ended. The same social class distinctions that existed between Genevra and Fitzgerald are examined in detail in The Great Gatsby, and the rich upper class is condemned as being snobbish and amoral.
Finally, the novel is rich in its depiction of the Roaring Twenties as the era played out, especially in New York. Fitzgerald and Zelda lived in New York after their marriage, caught up in the frenetic, excessive lifestyle, spending money as fast, or faster, than Fitzgerald could earn it. The automobiles, music, fashions, occupations, wild parties, and gorgeous mansions detailed in the novel were part of their daily lives. (Fitzgerald himself named the era "The Jazz Age.") For a while, he and Zelda lived in a fine home in Great Neck, New York, on Long Island, their estate being a place very much like Gatsby's West Egg estate, the scene of his opulent parties where all manner of guests showed up.
The Great Gatsby is a work of fiction, but clearly it was born of Scott Fitzgerald's own life and many specific experiences. It is impossible to imagine that anyone else could have written it.
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