The decades between the Civil War and World War I were also an epoch of rapid population growth and urbanization. Between 1870 and 1900 national popu… - Robert D. Putnam

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The decades between the Civil War and World War I were also an epoch of rapid population growth and urbanization. Between 1870 and 1900 national population nearly doubled from 40 million to 76 million, while the population of cities tripled from 10 million to 30 million.
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Year after year an endless stream of hopeful emigrants from American farms and European villages poured into the anonymous teeming cities of tenements and skyscrapers. These migrants were living now not merely in a new community, but in a setting so unfamiliar and disjointed that many doubted it deserved the term community at all.
Most of the new urban dwellers were also living in a new country. In the thirty years between 1870 and 1900, nearly 12 million persons immigrated to the United States, more than had come to our shores in the previous two and a half centuries. In the following fourteen years nearly another 13 million would arrive. In 1870 one-third of all industrial workers in America were foreign born. By 1900 more than half were. In 1890, immigrant adults actually outnumbered native adults in eighteen of the twenty cities with a population over 100,000.
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To those who lived through this epoch, what was most striking was simply the overwhelmingly accelerated pace of change itself. We often speak easily about the rapid pace of change in our own time. However, nothing in the experience of the average American at the end of the twentieth century matches the wrenching transformation experienced at the beginning of the century by an immigrant raised as a peasant in a Polish village little changed from the sixteenth century who within a few years was helping to construct the avant-garde skyscrapers of Louis Sullivan in the city of ‘big shoulders’ besides Lake Michigan. Even for native-born Americans, the pace of change in the last decades of the nineteenth century was extraordinary. A Bostonian Henry Adams later wrote of his own boyhood, ‘The American boy of 1854 stood nearer the year 1 than t