In American history, the "Gilded Age" refers to major growth in population in the United States and extravagant displays of wealth and excess of America's upper-class during the post-Civil War and post-Reconstruction era from 1876.
The wealth of the period is highlighted by the American upper class's opulent self-indulgence, but also the rise of the American philanthropy (Andrew Carnegie called it the "Gospel of Wealth") that endows thousands of colleges, hospitals, museums, academies, schools, opera houses, public libraries, symphony orchestras, and charities.
The Beaux-Arts architectural idiom of the era clothes public buildings in Neo-Renaissance architecture.
The term "Gilded Age" had been coined by Mark Twain and Charles Dudley Warner in their book, The Gilded Age: A Tale of Today (1873).
