Sherman Marches Through Georgia
The divisions between the CSIPers, the Constitutional Democrats, and the True Whigs were quite simple. Simply put, the non-commissioned military officers, upscale immigrants, US-linked businessmen, and non-slave-holding yeoman farmers were the backbones of the CSIP. The True Whigs were largely powered by small yeomen farmers and planters outside of Appalachia, men who typically owned only a few slaves, or owned no slaves, but rented a slave from a large planter and aspired to be large planters one day. The Constitutional Democrats were of course, overwhelmingly dominated by the wealthy large and mid-sized planters of the Confederacy. This class division ultimately heavily favored the Constitutional Democrats and as soon as the CSIP administration collapsed in the wake of various corruption scandals and the Alabama War, the Constitutional Democrats were able to seize control of politics quite easily, as the CSIP never had a mass base of support and the True Whigs had many of their supporters co-opted by the Constitutional Democrat's aggressive foreign policy.
Broadly speaking, 1% of whites were elite planters (owning over 40 slaves), 5% larger-sized (10-40), 5% being mid-sized (5-10), and 7% being small, owning 1-4, and 7% not owning any, but renting out a slave from a large planter. Of the other 75% of the country, the urban middle-class was around 5% of the population (and disproportionately immigrant). Then 15% were non-slave-holding yeoman farmers (disproportionately in Appalachia and Texas), 20% modest landless farmers, and 35% from the excluded class, which would be instrumental to the end of the First Confederate Civil War.
That extremely deprived class of whites were not engaged by the CSIP and later totally disenfranchised by the Constitutional Democrats. This class of poor whites generally owned no property, slaves included. No land, no slaves, and often no savings. Another roughly 20% of white Confederates also owned no slaves and no land, though they had some modicum of savings. Before the Civil War, they were effectively disenfranchised in most of the slave states, were banned from reading abolitionist literature, and could be executed for engaging in anti-slavery speech. They formed a class of labour that was neither free nor unfree - they were not slaves like blacks, but they were often arrested (poor whites filled most Confederate jails) and rented out as convict labor. They often became indentured servants. Andrew Johnson's hatred of the Confederacy was driven by his unhappy childhood growing up as a poor white in the South, when he was sold by his widowed mother as an indentured servant.
Wealthy planters often feared this group. They overwhelmingly sided with the Union in the War of Independence, and when county secession conventions weren't properly rigged, they had a tendency of voting against secession, as seen by the state of West Virginia. The tone of the Confederacy was very much set in 1860, when Southern political elites prevented Abraham Lincoln from being on the ballot, out of fear that this class would vote for him! The only slave states where people were allowed to vote for Lincoln was Delaware, where he scored a respectable 24%, and Missouri, where he did less well at 10%, but partly because the two other Unionist candidates scored over 70% of the popular vote. Without even counting unfree blacks, had all whites been able to vote on whether to leave the United States, the result would have been a landslide for the Union. Although they were drafted into the Confederate Army, they were not particularly supportive at all of the Confederate project. However, they never organized in the years after the war, because they were overwhelmingly illiterate. Although it was legal to teach them to read (unlike slaves), in practice, the lack of any public education prevented any mass education. In addition, Southern crime was notoriously harsh even before the Civil War - the justice system overwhelmingly targeted these whites, not blacks (who were still enslaved).
The Christian Commonwealth of North Carolina was many of the fears of elite planters coming through. Although Jackson had the support of the Lumbee and many freed slaves, the bulk of his support were poor, landless, white peasants, who gladly abolished slavery, not because they wanted slavery abolished, but because they simply wanted to spite the social elites. However, Jackson kept them on a tight leash, and North Carolina was a relative bastion of stability. This was not to be true in the rest of the country.
The 6% of elite planters and larger planters actually split down the middle, largely between people who were truly ideologically committed to slavery and those who primarily cared about their bottom line. As did the slave-renters, who overwhelmingly aspired to slave-holding, but split down on the middle as to whether they cared enough to side with the Provos in the middle of a war against Spain. However, the mid-sized and small-sized planters overwhelmingly sided with the Provos. This gave the Provos a base in around 20% of the white population. In contrast, the non-slaving yeomen farmers (15%) sided with the Nationals, as they were probably the closest thing the South had to a group positively disposed towards abolitionism. The urban middle-class did as well, due to their obvious proximity to industry (5%). Finally, the minority of planters not covered above sided with the Nationals (around 5% of the population). Finally, the modest landless farmers (20%) sided with the Nationals, largely because they revered the Confederate Army as their primary path of social mobility. This gave the Nationals a solid base of around 45% of the white population.
In many ways, this would have simply been an easy, quick defeat of the Provos. However, the calculus got even worse for the Provos, when poor, deprived whites, included in neither major coalition, spontaneously exploded in rage across Georgia, North Florida, and parts of South Carolina at the excesses of several Provo mobs, who were attacking anyone associated with the Nationals. Combined with their deep economic suffering due to the massive explosion in food prices, a fire was lit. Attacking the Provos as "satanic traitors to the Confederacy, puppets of Mammon", poor whites across Provo territory, inspired by Jackson's fervor but not restrained by Jackson's charity, formed even larger mobs that overran both the Provo mobs, but also Provo arsenals, seizing weapons, and destroying, looting, and burning any center of wealth they could find. The Provos, unable to fight both an internal revolt within a revolt at the same time they tried to fight the CS-US Armies, quickly collapsed. The vast majority of slaves simply bolted to defend themselves, with the kinder masters sometimes finding out that their former slaves, while empathetically pointing out that they were finally free, would help them escape the mobs. The crueler masters were much less lucky. In some cases, former Provos too far from Spanish areas of control celebrated the arrival of General Sherman, who typically dispersed rebels and re-established social order as his army marched through Georgia. Those closer to Spain quickly fled into Spanish-protected areas, causing Spanish-occupied Savannah to expand in size.
Ironically, the ideologues of the Confederacy had spent years asserting that the collapse of their rule would lead to widespread massacres, rapes, looting, and other atrocities. They were entirely correct, as every major city in Georgia except Savannah (under Spanish protection) was burnt down in an orgy of violence and looting. They were wrong in supposing that such atrocities would be committed by blacks. Savannah, Alexandria, Columbus, and Atlanta all burned down, with Spanish-occupied Savannah as the Confederacy's new largest city and port. The rebels were often merciless, lynching civilians associated with the Provos and even some Nationals (if they looked sufficiently rich) in the thousands. One oddly semi-educated rebel leader famously adopted as his group's slogan: "Caedite eos. Novit enim Dominus qui sunt eius." Latin for "Kill them all. God will recognize his own." The noose would from this point on forever be a symbol of revolutionary extremism in North America. The only reason the CS-US armies could defeat the rebellion was that the extremism of these minority of rebel bands quickly turned the majority of rebel bands against them and towards accommodation with the CSA. Some had espoused opposition to both the Nationals and Provos, but the most extreme bands convinced most of the rebel bands to support the Nationals, following the example of the late Stonewall Jackson.
Ironically, escaped slaves were typically not the source of the worst atrocities. Although there were many recorded incidents, most slave groups simply banded together and tried to hide out in the wilderness, sometimes helping out individual whites, sometimes not. Luckily, the most insane of the escaped slave bands had a tendency of fighting with the most insane white rebels, and the fact that the two groups tended to kill each other off through increasingly brutal methods tended to limit the atrocities inflicted on everyone else. Stories of escalating atrocities between these two groups, including flagellation and mass sodomizations, were luckily ended by the arrival of US/CS troops, which had a tendency of crushing both. As a result, although the USA remained relatively unpopular in the South, General Sherman became wildly beloved in the CSA for his March through Georgia, because he was completely apolitical in mercilessly and methodologically crushing any group in the rebelling states, whether pro-National, pro-Provo, white, or black, that was committing atrocities against any other group. This extended to General Sherman protecting any Provos from reprisals, either from the rebels or Nationals.
With all of Georgia in ruins, order only partially restored, and the Spanish Army more or less running a giant refugee camp in Savannah, it also became clear to both the Spanish and the Confederates that it really was the time to start negotiating peace.