Between 1900 and 1915, more than 15 million immigrants arrived in the United States. That about equals to the number of immigrants who had arrived there in the previous 40 years combined. In 1910, three-fourths of New York's population were either immigrants or first generation Americans.
Not only were the number of immigrants increasing, the countries they were coming from were changing dramatically as well. The majority of newcomers after 1900 came from non-English speaking European countries, unlike earlier immigrants. The main source of immigrants were now southern and eastern Europe, especially Italy, Russia, and Poland, countries way different in culture and language than the US. The new immigrants had difficulty adjusting to life here.
The US had difficulty absorbing the immigrants. Most immigrants chose to settle in American cities, where jobs were located. As a result, the cities became even more crowed. City services often failed to keep up with the flow of newcomers.Most immigrants eventually found jobs, although it was work most native born Americans would not take. Over time, the immigrants succeeded in bettering their conditions.