In general, the Industrial Revolution led to a situation in which cities became more stratified in terms of class. Class was often connected to ethnicity, but ethnicity also had an independent impact on residential patterns. This led to the creation of cities in which the rich were segregated from the poor and in which people of different ethnicities tended to live together in homogeneous neighborhoods.
Before industrialization, there was less of a gap between rich and poor and cities were not very segregated on class lines. With industrialization, however, this changed. Factories attracted large numbers of relatively unskilled workers who were typically fairly poor. They also created middle and upper classes. These classes came to live in separate areas. This became even more pronounced as streetcars and other forms of transportation allowed richer people to live farther out from the city centers.
Many of the poor were “white ethnics.” These were people who had typically recently immigrated to the US. They did not, however, tend to live in a big “melting pot.” Instead, people of each ethnicity tended to live together. This gave rise to many ethnically homogeneous neighborhoods with names like “Little Italy.”
Thus, industrialization created cities that were rather segregated by both class and ethnicity.