The Centralization of the NYC in Manhattan could have potentially slowed down the economic success the city was experiencing if nothing was done to de-centralize Manhattan in the city. Population was rapidly growing creating tension between different ethnic groups that were forced to live together in the crowded and run down tenements that the city provided (link to various pictures of tenements) causing different ethnic groups to be scattered around the city. Although some had found their niche in the city already, they were not very large concentrations of the different ethnic groups because of the inability to move relatively freely around the city. When the IRT created subway lines that branched out from the center of the Financial district in Lower Manhattan, the different ethnic groups could begin to find areas of the Brooklyn to claim as their own. The five cent fare to use the subway was another factor which allowed people of all classes to ride the train. People traveled on the trains just for the enjoyment of riding a creation of modern technology and because of the safe atmosphere it had. All kinds of people rode the trains at the same time regardless of what race or ethnicity one was; blacks rode with whites, Irish, Germans and all other ethnicitys present in the city.The trains created a world different from that of the city and this would be essential in the trains role in NYC, when it would provide access for different ethnic groups to relocate themselves around Brooklyn.

African Americans were one group of people that stayed in Brooklyn despite the rapid growth of African Americans in Harlem along with Germans and Italian Americans who carved out their own areas in Brooklyn in Williamsburg, Stuyvesant and parts of Brooklyn Heights. They were able to live in this area because of the ability to commute to and from the Lower east side where the factories were. Germans who were considered the smarter ethnicity could travel to the financial district for business and development using the IRT line connecting Brooklyn to Manhattan.