Twice as many as for the North, most as Free Blacks or in contemplation of freedom. Many saw a chance for their own State. They saw none for freedom under the Northern States that did not in most cases let Free Blacks live there. The Confederate flag is no intended symbol of oppression. The issue was not racism.
Racism is prejudice merely from skin color.
Here, it is an anachronism. The real problem was mass assimilating Slaves into a freer culture post-slavery. Very few thought that could be easily or quickly done, including Black leaders such as Frederick Douglass. He proved right. He believes with Jefferson that, along with Gibbon, Cicero and Tacitus should be read by all grade-schoolers.