There are many parallels between F. Scott Fitzgerald's life and that of his characters in The Great Gatsby. Indeed, Fitzgerald was born in the Midwest but moved to the East, always felt insecure in his position in Eastern society, and felt himself capable of observing others with an objective perspective - characteristics he shared with Jay Gatsby. As did Gatsby, Fitzgerald spent time in the military during World War I. He met the woman who eventually became his wife while he was in training camp in Alabama - similar to the situation between Gatsby and Daisy but with a different conclusion.
Fitzgerald and his wife lived on Long Island at one point in their lives. They entertained lavishly, with extravagant amounts of of liquor and elaborate decorations and entertainment. Their guests included wealthy individuals and those involved in the arts - the types of people portrayed in Tom and Daisy, Jordan, and Gatsby himself.
The people surrounding the Fitzgeralds and the people surrounding Gatsby were largely examples of the Lost Generation - interested in having a good time, self-centered, unconcerned about how their actions affected others, willing to try anything that might give them pleasure or help them acquire more money.
In the original version of his 1936 short story "The Snows of Kilimanjaro," Ernest Hemingway wrote,
The rich were dull and they drank too much....They were dull and they were repetitious. He remembered poor Scott Fitzgerald and his romantic awe of them and how he had started a story once that began, "The very rich are different from you and me." And how some one had said to Scott, "Yes, they have more money." But that was not humorous to Scott. He thought they were a special glamorous race and when he found they weren't it wrecked him as much as any other thing that wrecked him.
Certainly, Hemingway's description of Fitzgerald fits the character of Jay Gatsby, who also is "wrecked" by the careless Daisy and Tom Buchanan. Gatsby pursued this "glamorous race" as a superior force. When, for instance, Gatsby wants to join the Sloans in Chapter Six, they act as though they are glad to have him; however, in private they are repulsed by the nouveau riche Jay Gatsby, and they sneak away before Gatsby comes back out to follow their horses with his car.
Similarly, Gatsby is left behind by the Buchanans. After Daisy runs over Mrytle Wilson, Gatsby heroically tries to take the blame for Daisy, and he stands outside in the moonlight in a "sacred" vigil. When Nick leaves him standing in the yard, Gatsby is "watching over nothing." Similarly, when Fitzgerald compromised himself as a writer in Hollywood, he, too, was "watching over nothing" and failed to ingratiate himself with influential people.
The frivolous Daisy is similar to Zelda Fitzgerald, the daughter of an Alabama judge. Fitzgerald met Zelda while he was stationed at Camp Sheridan outside of Montgomery, Alabama, a situation similar to that of Jay Gatsby, who met Daisy while stationed in her town. And also like Gatsby, Fitzgerald left life in a tragic manner.