First of all, we should note that most of the immigrants became American industrial workers during this time. Therefore, it is accurate to say that immigration created many American industrial workers. Immigration greatly increased the number of American industrial workers.
The major impact of the immigration was to reduce the power of the industrial worker. The huge influx of immigrant labor meant that there was a plentiful supply of people who were willing to work in the factories. Because of this, the employers enjoyed a buyer’s market. If some workers did not like their wages or conditions, they could easily be replaced from the huge pool of labor that was constantly being augmented by immigration. This meant that employers could mistreat workers and workers could do very little about it. In this way, immigration hurt the American industrial worker by making it harder for them to have any leverage over their employers.