how do the settings in the novel represent the attitudes in america at the time the novel was written ?
A term coined by Fitzgerald himself, the Jazz Age was one like the music--edgy, improvisational, and seductive in nature. The "flappers" were young women who broke from the Victorian ideal of womanhood by frequenting speakeasys and going to nightclubs and other places where women were hitherto not seen. It was an era of freewheeling spending and amoral behavior.
The Roaring Twenties were a free-wheeling time, but the book depicts a less pleasant view. There is a certain amount of judgment in the book’s description of wealth and decadence. The characters, who focus on image and wealth, are basically immoral. There is gluttony and debauchery everywhere.
The opulence of Gatsby's mansion is representative of a certain, new vision of wealth. We might call the new materialism, due to its extreme degree, a new aristrocracy. As a setting, the mansion serves as a demonstration of the public view of wealth and fame as the guests "ooh and ah" about the estate.