Since 1860s, the United States of America has been receiving constant and massive waves of immigration from various European countries. Before 1930s three and a half million British people came to live in the U.S. At the same time, four and a half million of Irish immigrants arrived to America saving themselves from the outcomes of the Great Famine that hit their rural areas in 1845.
Mass starvation and poverty became intolerable, so millions of families had to leave their country looking for better life. In total, around twenty five million of Europeans moved to the United States by the beginning of the twentieth century. These were the immigrants from Eastern and Central Europe, from the countries such as Italy, Hungary, Poland, Czech Republic and Greece.
At least four millions of the immigrants were Jews. Another large wave of immigration of the refugees of World Wars and disorders happening in the former Russian Empire occurred in the end of the nineteenth and the beginning of twentieth century.
The flow of immigration headed mostly to urban areas and big cities such as New York and Boston. Immigrants from Sweden, Norway and Germany settled in the Midwestern states such as the Dakotas and Minnesota. Detroit received a large number of Middle Eastern Muslim immigrants.
The newcomers were mostly feared and unwelcome in the American society. Immigration caused a large wave of American xenophobia and groups such as the American Republican Party, promoting regulations and restrictions for immigrants, started to appear. Some of the fears were based on religions practiced by the arrivers. For example, European Catholics were thought to be hostile and controlled by the Pope.