By the Numbers: Rise of the Black Ghetto; March 2004; Scientific American Magazine; by Rodger Doyle; 1 Page(s)

The North was once alive with the abolitionist spirit and open to the possibility of integration. Yet this passion yielded to several forces that marginalized African-Americans in the 20th century.

Before World War I, blacks were relatively few in the North, which together with people's need to be near their factories and offices, helped to reduce any tendency toward housing segregation. In New York City, for example, largely black neighborhoods were usually only a few blocks long and interspersed with the homes of working-class white families. The modern ghetto, with its sharply defined racial lines, generally did not begin to form until blacks in substantial numbers migrated north beginning in 1916. There they found themselves competing for jobs and housing with immigrants from Europe. The competition was often violent, as in the Chicago riot of 1919, when 38 people were killed. Violence and the threat of violence, together with agreements among white homeowners not to sell to blacks, increasingly left African-Americans in separate neighborhoods.