Modern America: Industrialization, Urbanization, Immigration
Following the Civil War, the United States emerged as an industrial power. Rapid industrial growth led to increased demands for fuel. The fuel of choice became anthracite coal. As a result, people began to migrate to urban areas in search of work. The effect was two-fold: workers in the cities needed fuel to heat their homes, and the increased availability of labor heightened production. Additionally, a rapid influx of Eastern European immigrant workers led to greater nativism among the established Western European population.
segment from "Stories from the Mines: How Immigrant Miners Changed America"