Schomburg Center for Research in Black Culture. A negro family just arrived in
Chicago from the rural South. 1922. The New York Public Library Digital
Collections
The Great Migration was a period between 1916 and 1970 when 6 million African Americans moved out of the Southern U.S. to the north, where there were better job opportunities and less discrimination.
Schomburg Center for Research in Black Culture. A negro family just arrived in
Chicago from the rural South. 1922. The New York Public Library Digital
Collections
African American Migration, 1915-1970. Pearson Education, Inc, 2003
A map of the US depicting the movement of African Americans during the Great Migration
"The prime cause is higher wages in the North, coupled with the stagnant condition of southern industries. Here wage increase has been only occasional, although in this community in the past six months, since the movement has begun to be felt, wages have gone up from 15 to 25 per cent. But the cost of living has risen faster than wages. Contributory influences include labor agents, need of better schools and better police protection, and lack of incentive."
~R. H. Leavell on the causes of migration
Beveridge, Andrew A. Population and Racial Composition Harlem and New York City, 1910 to 2006. Gotham Gazette, 2 Sept. 2008
Harlem was an upper-class white neighborhood, but it was overdeveloped and landlords needed to fill up vacancies. So, they offered housing to middle-class African American families. Harlem natives resisted the African Americans moving to the neighborhood but when their resistance failed, they moved away.