"new money." During the Gilded Age, members of the "new money" class enjoyed unprecedented wealth and opulent lifestyles, which many "old money"

Edith Wharton was born into New York's upper-class establishment and was well-equipped to give the world an inside look at the lives of New York's snobbish upper classes. Born during the American Civil War, Wharton grew up in an established New York family that enjoyed the privileges of generational wealth and meaningful social connections.
During her childhood, a vast expansion known as the Gilded Age radically transformed cities throughout America. New York, in particular, went through rapid industrialization and modernization. New industries and technologies sprung up overnight, creating a new set of powerful and wealthy families. Since these families had not inherited their money and were not of the privileged lineage that dominated the upper classes in New York, they were looked down upon as "new money."
During the Gilded Age, members of the "new money" class enjoyed unprecedented wealth and opulent lifestyles, which many "old money" class viewed as vulgar and tasteless.
In The House of Mirth, Edith Wharton drew on her background to explore themes of social class, gender, and the emptiness of materialism.
Class and Materialism
Lily has grown up in the upper classes of New York society; however, shortly before her father's death, he announced that he had lost the family fortune, leaving Lily with a precarious future. She knows that to maintain her social standing, she must marry or make her fortune. No alternatives exist for a woman like Lily, so her actions throughout the book are driven by social pressure to secure wealth and status.
Wharton uses The House of Mirth to critique the shallowness of New York’s high society and its obsession with wealth. Although Lily sees people like the Trenors and Dorsets as her social betters, they are in reality morally bankrupt and petty. They scheme and conduct affairs while judging Lily's actions and spreading false rumors. Still, Lily is trapped in this social class and cannot forge her path in the world.
Lily has several chances to live a comfortable life with any of her potential suitors but keeps turning them down in the hope that a wealthier bachelor will come along. Even as she falls down the steep social ladder and can barely make ends meet, Lily still strives to fulfill her social obligations by ensuring she pays off her debt. Ultimately, Wharton uses Lily's story to warn about the dangers of pursuing materialism and trying to live up to others' expectations.