Immigrants arrived in this country and by hard work soon became prosperous. Then they sent passage-money to their friends and relatives until whole groups of families were enabled to come to America in this way. The steamship companies, too, have advertised the attractions of America in all parts of Europe; they have kept agents at work in many countries, and have been an important factor in promoting immigration. [Sidenote: The economic factors have been the most important.] Nevertheless the underlying causes of immigration are economic. Immigrants come in greater numbers when prosperity reigns in America than in periods of business depression. This indicates that high wages and plenty of employment are the things which have the greatest influence in bringing them here. The democratic institutions of America have played their part, no doubt, and the relative social equality which exists among the people of the United States has been an attraction to those who are denied such equality in their own homelands. But the equality of economic opportunity, the open career, the chance of making a good living and even a fortune—these, after all, have been and still are the impelling forces. [Sidenote: How the immigrant has affected American life.] =The Effects of Immigration.=—A large immigration is certain to have far-reaching effects, particularly if the newcomers be of a widely different race. It has assuredly had far-reaching effects in the United States. Take the importation of the negroes as the most conspicuous example. The coming of several hundred thousand persons of African blood, during the years preceding 1808, has resulted in placing a colored population of more than ten millions in the heart of a white man’s country, with all the social, economic, and political problems that this situation implies. It influenced the agricultural system of the Southern states, provided the underlying causes of the Civil War, and has profoundly affected the politics of the United States down to the present day. The problem presented by the immigration of the various European races has been altogether different because these races can be assimilated whereas the negroes can not. Even so, the European immigration has presented its own problems and the coming of these many millions has had profound effects upon every branch of American life. [Sidenote: The making of a composite race.]