During the "Gilded Age", from the 1870's to about 1900, John Singer Sargent painted his masterpiece "Madame X", electric lighting was invented, and with the expansion of the transcontinental railroad, you could now travel from New York to San Francisco in six days, where previously the journey had taken six months. 10 million immigrants arrived in the USA, labor unions put more power in the hands of the working man (and woman), and the wealthiest families in New York (the Vanderbilts, Rockefellers, and Carnegies) built spectacular mansions. "The Gilded Age" was a term that referred specifically to America - the US, at this point, jumped ahead of Europe in terms of wages and the speed of industrialization. It coincided with the Victorian era in the UK.