Answer:
The late 19th century was marked by rapid urbanization in the United States. With the rise in the number of factories in the United States, as well as the increase in immigration due to the spread of steam ships and quicker modes of oversea travel, and also due to famine and disease in Europe and other parts of the world, the rise of major cities greatly affected the United States.
New York City in particular is known for the number of immigrants it hosted at the time, as well as the increase in so-called "tenements" that were really just glorified slums. They were cheap, and since most immigrants had very little income, and no way to increase that income, the tenements were really all they could afford. They were dirty, overcrowded, and filled with disease.
Most impoverished Americans in urban areas, especially those living in the slums and tenements, had little to no access to education. This meant that were usually unable to read and write English; immigrants, especially adult immigrants, couldn't always <em>speak</em> English, either.
The rise in immigration caused little sections to form in almost all the major cities. "Little Italy", "Chinatown", etc. were what they were often called. Even today, if you go into a major city, such as San Francisco, New York City, or Philadelphia, you can still often find the little sections of town where immigrants from the same countries, with similar backgrounds, who usually all spoke the same language, settled near each other, so this new world felt a little more like home.
The sudden increase in urbanization in the US forever changed the infrastructure of the entire country. What was once mostly farmland and little villages quickly became a country filled with rapidly growing cities, factories, high-rise buildings, and a <em>huge</em> influx of immigrants from all over the world.
Things that before, the American people would have never thought possible, were happening, all thanks to the laborers in the factories of New York City, Philadelphia, and many other cities around the country. New modes of transportation were making it easier than ever to travel all the way from San Francisco, California to Pittsburgh, Pennsylvania. While working and living conditions for the factory workers, immigrants, and impoverished people in the cities were truly awful, in other ways the United States was moving forward and growing more powerful than ever before.
I hope this helps! Thanks :)