The Custom of the Country is a 1913 tragicomedy of manners novel by the American author Edith Wharton. It tells the story of Undine Spragg, a Midwestern girl who attempts to ascend in New York City society.
The Spraggs, a family of newly wealthy midwesterners from Apex, arrive in New York City to advantageously marry off their beautiful, ambitious, and temperamental daughter Undine. Attracted to glamour and extravagance Undine has a hard time making inroads into the high status old money social circles she wishes to enter. Her beauty catches the attention of several men who offer her a tantalizing glimpse into their world. Ralph Marvell, who is descended from the Dagonets, an old money family, becomes attracted to Undine. Convinced that Undine is a simple and plain spoken girl who would be ruined by her elevation in society, he resolves to quickly woo and marry her. However, Marvell is an unsuccessful lawyer and a would-be poet, and his family no longer has great reserves of cash. Before the marriage, his grandfather informs Mr. Spragg that Spragg will have to financially support the couple. Mr. Spragg asks Undine to end her engagement but Undine, now aware that the Marvells and the rest of their social circle highly value sexual purity and frown upon broken engagements and divorce, refuses to leave Ralph, and her father relents to the marriage. Shortly before her wedding, Undine encounters an acquaintance from Apex named Elmer Moffatt. Undine begs him not to make their acquaintance known as it could compromise her relationship with Ralph. Elmer agrees, but later, he approaches Mr. Spragg and leverages the fact that the Spraggs are embarrassed to know him to coerce Mr. Spragg into a business deal that profits them both greatly.