Mark Twain coined the term the "Gilded Age" for this period of growth and extravagance, experienced most dramatically in New York City from the 1870s to 1910. More than half of America's millionaires lived in the city.

Previously unimaginable sums of money were made and spent, while poor immigrants toiled away in tenements. Author Esther Crain writes, "There was an incredible energy, a sense of greatness and destiny. Things were literally going up-skyscrapers, elevated train tracks, new neighborhoods and parks. Accompanying all of that was an equal amount of greed and lust. Crime, vice, political scandals-the Gilded Age produced an abundance of depravity."