My theory - for the longest time Blacks while suffering under things like straight up racism, segregation, etc. retained their faith in God(Jesus) so they couldn't be dragged down like the racists wanted even in the face of death. So racists, mainly the democrats/dixiecrats/racists, came up with a plan - to get Blacks away from Jesus and to become reliant on government namely the democrat party.
And if ANYONE believes it can't happen to Whites better guess again! What happened in Minnesota is exactly because of Whites who became dependent on democrats and/or government.