Why did Northern European people come to settle down in the United States?

After the early period of settlements, the first sharp increase in immigration took place in the 1830s and 1840s. This brought to America flocks of people from northern Europe who lost employment in the Industrial Revolution, and then a great number of Irish people who fled from famine. German political refugees arrived shortly after. In the 1880s, a tremendous flood of immigrants began coming in, this time largely from southern and eastern Europe. To most Americans, these newcomers seemed far stranger than the early settlers. They moved into the poorest neighborhood of the large cities. They tended to stay together and cling to their old ways. As they were accustomed to poverty, they were willing to work for very low wages. This made other workers, especially those in labor unions, afraid that the immigrants with the lower wage level would take jobs away from them. Indeed, organized labor became one of the key opponents of continued immigration.
    This opposition finally led to the passing of immigration laws in the 1920s, which restricted further immigration. In 1965, these unfair laws were replaced by a new immigration act, which granted equal opportunities to foreigners, regardless of their place of origin. Asians, like Koreans and Vietnamese, soon began to arrive. Many of these newcomers have worked very hard to establish themselves in their new land.