the movement of immigrants related to industrialization, because the immigrants allowed the monopolies to have cheap labor. So, they had a larger quantity of workers with a lower pay salary. Also, with more workers the industries could manufacture and produce more materials and sell them at different prices
Adolf Hitler.
The middle class
the development of industrilization
Europe
many things became mass produced.
ca[itol technology transportation and energy
Urgent need for war supplies of every sort.
They both were not for immigrants coming in to the United States.
They were pretty reasonable. See related questions for further information.
Many U.S. immigrants have come from Germany and Greece.
some groups of immigrants are Spanish, European, and Asian. The reasons why they immigrated were mainly to have a better life, also religious freedom or other reasons related to self security purposes.
Paradoxically, because illegal immigrants help many corporations. See related questions.