History professor Carol Swain talks about it some here:
Why Did the Democratic South Become Republican?
https://youtu.be/UiprVX4os2Y
Except they didn’t.
Louisiana is still only 33% Republican.
We have been growing from 0% in 1972 at a linear rate.
The democrats have been falling from 97% down to about 45% today.
And the only reason the democrats gained that dominance was through threats, violence and murder.