A Black south or an alternate reconstruction

Given the previously unprecidented degree of mobilisation of African -
American troops by the North during the civil war (I undestand around
40% of the troops fighting for the north were black by the end of the
civil war .) , what if large numbers of Black soldiers had stayed and
settled in the south ? With substancial depopulation amongst southern
whites , and a large influx of Black settlers , the majority
population across large areas of the south would become Black
practically overnight .
The North , at the cost of a few weapon and large tracts of land they
didn't own or control in the first place , gets a permenant and
grateful occupation force to ensure that the south never "rises
again " , and de facto control established over large tracts of
lawless , rebel infested countryside without the necessity of
stationing massive military forces there on a permenants basis .
It also halts many of the developing racial tensions in the North by
effectively establishing an area where Blacks make up the majority .
Of course it creates waves of southern refugee's , although there
were already substancial numbers in the north anyway ...........
Can't see any major reasons why it Couldn't have happened .
Sympathy for the Rebel south was at a very low ebb and many
northerners would I think have appreciated the irony of such
a "punishment " .....

How would the establishment of large parts of the South effectively
under black domination have affected the subsiquent development and
history of the United states ?

How about this -

As a direct result of greater import of slaves, the percentage of Black to White Southerners is even greater. Then in the 1850's a series of slave revolts occur that grow in power and organziation.

Although southern militias are able to initially contain the revolts, planters and other whites send their families either North or into the mountainous areas of the south.

Finally, in 1856 the lid is ripped off the South when a Northerner named John Brown incites a successful revolt. Although John Brown is assassinated by a rival, the shear fury of the revolt leaves vast areas of the south empty of white slave holders, populated only by a few poor white farmers and a large number of self freed blacks.

Although US troops enter to pacify the area, within a few months the general opinion in the North is that the slaveowners got what they deserved, and efforts turn to stabilizing the Union.

The surviving southern whites are offered free lands and help in settling in the West, where they mix with other immigrant groups. Within a few generations, much of the resentment they felt towards what they initially called the 'dispossession' is gone.

In the black areas of the South, Union troops offer stability to otherwise unmanageable areas, and within month leaders have risen exhibiting a steadiness and desire to remain in the Union.

However, because of the initial resentment over the dispossession, Southern Whites and Blacks refuse to sit in government together, and the South is divided into several additional states cut from the body of the old South, including the predominately white Upper Carolina and Highmont (Georgia and Alabama). Black dominated states include Jerico, and Lower Carolina. Blacks remove from most border areas, such as Virginia, although there remains a fair minority of africans.

Union troops remain on the borders between black and white areas, but gradually, over the years, the hatred begins to die. Then in 1870, Spain approaches the US with the proposal to buy Cuba, which the Central Government does, mostly to ensure the black south has some areas that it can settle, which it does in great numbers. In 1885, Cuba joins the Union.

ooh very nice scenario idea!