What changes caused the great migration

The first (or most important) factors for moving (from one place to another) among southern African Americans were (separating things/separating people by race, religion, etc.), an increase in the spread of racist belief systems, (existing all over a large area) murder (by hanging by the neck) (nearly 3,500 African Americans were hung (by the neck) between 1882 and 1968), and lack of social and money-based opportunities in the South.