Answer: Well, according the the all-knowing Googs:
"Immigration to the U.S. in the Late 1800s. Between 1870 and 1900, the largest number of immigrants continued to come from northern and western Europe including Great Britain, Ireland, and Scandinavia. But "new" immigrants from southern and eastern Europe were becoming one of the most important forces in American life."
However!! Uh, There is no 'however', but I hope this lazily-obtained answer helps you, and if it does not, then comment and I will scour the internet for the answer in which. you. seek.