The 1880s ushered in a new era of immigration, with growth in both numbers and diversity of origins of the immigrants. With the advancing industrial revolution, demand for labor grew and so did immigration. From 1860 to 1880, about 2.5 million immigrants entered the United States each decade; during the 1880s, the number more than doubled to 5.2 million. In the first decade of the new century, 8.8 million entered the country, with a record of 1.285 million entering in 1907 alone. Only the decade of the 1890s saw a reduction over the previous decade's levels, largely because of the economic depression that affected much of the U.S. economy.

The origins of the new immigrants shifted with the growth in numbers. No longer were immigrants coming only from the British Isles and western and northern Europe; many of the newcomers came from southern and eastern Europe. In the first decade of the twentieth century, more than 2 million Austro-Hungarians, a like number of Italians, and 1.6 million Russians immigrated, accounting for more than 70 percent of all immigrants. Britain, Germany, and Ireland accounted for only 6.5, 4.2, and 4.2 percent, respectively. Some came for permanent residence, particularly groups, such as the Jews, who had been persecuted in Europe, whereas others were “birds of passage” who intended to work for a few years and then return home.