North Carolina had a large proportion of freedmen, and these had, until 1835, been permitted to vote.
As antebellum slavery became more lucrative, freedmen’s rights were diminished, and limitations on them became greater.
The slave power continued to enforce slavery over a population that became increasingly white due to the frequent rape of slave women by white masters and overseers, so much so that some poor whites were captured by slave catchers, and sold into slavery, with paperwork forged as necessary. Mostly white female slaves sold at a premium into the brothels, and were very popular with the southern gentlemen.
After the war, to the extent possible, defeated southerners tried to reestablish the antebellum conditions via the KKK, or through black codes, literacy tests, harsh sentences to plantation-jails such as the infamous Angola prison. Mass murders of blacks occurred such as the Rosewood Massacre right after a KKK rally at Gainesville Florida in 1922. Southern Democrats were long able to use southern mythos to block federal laws to punish lynching. Blacks were routinely prevented from voting, serving on jury, or serving in civil service positions.
“As antebellum slavery became more lucrative...”
This is an important point, because before the popularity of the cotton gin, slavery was pretty much dying as an institution. Slaves were limited to the upper classes, being relatively very expensive, and about half were domestic servants. Troublesome slaves were “sold down the river” (the origin of that expression), to do (very) hard labor on the delta sugar cane plantations.
But plantation economics were very different than imagined.
To start with, there were several periods of time when large amounts of field work was needed: planting, weeding, harvesting, then both transporting to market and processing for food storage, and brewing beer and distilling liquor, which was “rural currency” for excess crops, and for when potable water was not reliable.
And though itinerant work gangs would sell cords of wood for fuel, its use required a lot of wood chopping, hauling and fire stoking and cleaning. Likewise, recent archaeology has noted that main plantation buildings had water towers next to them, that must have taken a lot of water, and labor, to fill.
Likewise the slaves themselves needed cooked food, water, shelter, etc., that had to be provided for.
Everything that could not be fabricated had to be purchased, which meant either that the plantation had to be profitable, or would diminish the assets of the plantation owner, who likely had to have other business interests.
And these could be roller coasters. Leading up to the Panic of 1819, commodities prices became very inflated, so plantations would get a great inflow of cash. But with the panic, prices collapsed.
This was so onerous that by 1828, South Carolina created the “nullification crisis” against the “Tariff of Abominations”, the Tariff of 1828.
“The major goal of the tariff was to protect industries in the northern United States which were being driven out of business by low-priced imported goods by putting a tax on them. The South, however, was harmed directly by having to pay higher prices on goods the region did not produce, and indirectly because reducing the exportation of British goods to the US made it difficult for the British to pay for the cotton they imported from the South.”
And thus slavery was dying, but facing a new resurgence, with the arrival of the cotton gin around 1830.
Times improved considerably until the Panic of 1837, the worst depression until the Great Depression, which crashed the price of cotton and likely wiped out many plantations, and yet it accomplished two things, consolidating southern agriculture from many crops to just a few, mostly cotton, with production expanding from 750,000 bales in 1830 to 2.85 million bales in 1850.
But cotton was so profitable that slavery was no longer the domain of the wealthy, but was opened to middle class entrepreneurs, strictly interested in the bottom line. With just their own work in a single year, they could earn enough to buy a slave, which would double the land they could use to produce cotton. And with the profit from that, to double again. Soon they were wealthy.
And the demand for, and treatment of slaves became much, much worse.