Jay Gatsby, born James Gatz, is a character with enormous ambition. Because of this characteristic, he is able to rise from extremely humble roots as an unsuccessful farmer's son to a multi-millionaire with an opulent home on Long Island. In the intervening years, his fearless ambition takes him around the world as a first mate on a yacht, then into battle as a major in WWI, and finally into the world of organized crime. His ultimate ambition—to win the woman of his dreams—ends tragically.

Another notable characteristic of Jay Gatsby is his lack of social skill. This is attributable to his upbringing by poor and uneducated parents and the influence of Dan Cody while he was still an impressionable young man. Gatsby does not understand how to navigate a friendship with Nick, observable when he offers Nick a lucrative-yet-shady deal for simply agreeing to host himself and Daisy for tea. Gatsby also fails to see that there are social divisions among the affluent. He mistakenly believes that all he needs to offer Daisy is a life of luxury; he is oblivious to the value of the traditions and connections of the old money elite. Daisy in entrenched in a realm that will be forever off-limits to a nouveau riche person with a criminal pedigree, but Jay Gatsby does not have the social acumen to realize this.