Answer:
Southern and Eastern Europe.
Step-by-step explanation:
This wave of immigration lasted from 1866-1915 and brought 25 million to the United States, mostly from southern and eastern Europe. "Pushed" out of Europe by economic hardship and political persecution and "pulled" to the United States by the availability of jobs, these immigrants entered the country through gateways like Ellis Island and settled in America's teeming cities to take jobs made available by the Second Industrial Revolution.