
If place matters then the Great Migration represents the largest internal movement of any group in its striving towards a better life. Between 1920 and 1970 nearly 5 million Black Americans migrated away from the South. The men and women who were part of the Great Migration felt compelled to migrate to escape persecution and to search out economic opportunity.
Faced with injustices of Jim Crow and an ailing economy due to agricultural mechanization and government policy discouraging land use, Black workers found themselves migrating in record numbers. With increasing demand for industrial products to support war efforts, the Northeast & West coasts became a haven for Black migrants.
Northern companies offered well-paying jobs, free transportation, and low-cost housing to convince African Americans to move. They also sent labor recruiters to the South who received a fee for every recruit they provided for the company they represented.

In the 1940s alone, 1.4 million African Americans migrated—nearly as many as in the past three decades combined. Migrants worked in foundries, in meatpacking companies, as servants of the wealthy and on projects such as the expansion of the Pennsylvania Railroad. African Americans typically wound up in dirty, backbreaking, unskilled and low-paying occupations. These were the least desirable jobs in most industries. Still, the jobs often paid more than double than the salary in the South.
After the war, the demand for industrial labor slowed. The booming economy that once saw a rise in commercial goods to support the war efforts came to a halt as soldiers returned home from overseas. As factories reverted to peacetime production levels, a new crisis began.

Although the Great Migration offered relatively better economic opportunities than the Jim Crow South, blacks were still forced to adhere to a subservient role in society. While Blacks were beginning to establish a foothold in a rapidly changing industrialized economy, a new set of U.S. policies were establishing Black Americans as an underclass.
Kopf, Dan. 2016. Priceonomics. The Great Migration: The African American Exodus from The South.