Were you aware of this?
In a biography of John Hunt Morgan there is a reference to appreciation of Hegel. In general the slaveholding caste in the South can be described as “conservative” only in that they desired to ‘conserve’ the institution of slavery. Conservativism turns ut to be a relative term. Russian Conservatism in 1989 is a very different thing from American Conservatism in the present, and even that is relative. What we try to conserve even now is what the radical left has imposed on us continuously since President Wilson up to a dozen years before today.
The generation of Theodore Roosevelt and Woodrow Wilson was strongly influenced by Hegel and Darwin. In America, though, historicism was a move away from the founding tradition of natural rights. Under the influence of Hegel, the generation of Roosevelt and Wilson moved away from ideas of individual rights towards demanding a more powerful state and thinking that rights were not given by God or nature, but determined by social evolution and by government. It didn't help that Hegel wrote glowingly about "The State." He was a German whose university was controlled by the Prussian government. What we would call society or civilization or culture, Hegel and those he influenced called the state, and thus they accepted more power for the state than before.
This was roughly Harry Jaffa and the Claremont school's criticism of Hegel: the German philosopher turned away from the founding tradition of natural rights and put the state above the human individual. While Hegel and his successors were moving away from the idea that all men were created equal and endowed by their creator with certain inalienable rights, Southern slaveowners were coming to endorse a social model based on slavery and the denial of human equality. Whether or not Hegel was the source of the ideas of the supporters of slavery, the militant slaveowners certainly were part of the same current of opinion as Hegel and drew from the same pool of ideas, whether or not they actually read Hegel works.
Why did Southern militants need to draw on German thinkers? Because the American founders recognized the contradiction between the idea of natural rights and the institution of slavery and hoped that slavery would eventually go away. Pro-slavery thinkers wanted an ideology that would make slavery the foundation of civilization and liberty and they found much of what they needed in the historical relativism of the day. If Blacks weren't as evolved as Whites, a relativistic ideology would make it easy to deny them basic human rights. A tradition of natural or God-given rights makes it harder.
Jaffa overdid the identification of Calhoun with Hegel and Marx - Calhoun was almost dead when Marx started to make a name for himself. Jaffa overdid a lot of things, but he wasn't wrong in seeing a connection between Hegel and pro-slavery thought.