Answer: In the decades following the Civil War, the United States emerged as an industrial giant. Old industries expanded and many new ones, including petroleum refining, steel manufacturing, and electrical power, emerged. Railroads expanded significantly, bringing even remote parts of the country into a national market economy.
Industrial growth transformed American society. It produced a new class of wealthy industrialists and a prosperous middle class. It also produced a vastly expanded blue collar working class. The labor force that made industrialization possible was made up of millions of newly arrived immigrants and even larger numbers of migrants from rural areas. American society became more diverse than ever before.
Not everyone shared in the economic prosperity of this period. Many workers were typically unemployed at least part of the year, and their wages were relatively low when they did work. This situation led many workers to support and join labor unions. Meanwhile, farmers also faced hard times as technology and increasing production led to more competition and falling prices for farm products