During what is considered the largest wave of immigration in U.S. history, millions of overseas newcomers arrived from southern and eastern Europe, Russia, and Japan, seeking economic security, religious freedom, and other liberties. On the American continent, more than one million Mexicans migrated north between 1910 and 1920, seeking refuge from the violence and economic unrest in revolutionary Mexico. Though the labor power of this new wave of migrants was welcome at the turn of the century, the immigrants were often met with xenophobia.
At the same time that this wave of cross-border immigration occurred, Black Americans also migrated northward [ see also:The Great Migration: Black Americans move north, 1910-1930] in mass during the first decades of the twentieth century. Fleeing terror, violence, and inequity in the Jim Crow South, they too sought greater opportunities in the Northeastern and Midwestern industrial cities. Black migrants found that the color line shaped economic, political, and social life in these urban centers as well.
In the early twentieth century, ethnic identities became the focus of public debates, immigration policy, and “Americanization” campaigns for a homogeneous national culture.