Reputations of Pre-Secession (Pre-POD) Presidents
George Washington
Union: As a Virginian slaveholder with ties to the Lee family, Washington began to see a decline in popularity over the years, even if the idea of the US splitting in half would have horrified him. He was still listed as one of the "good" presidents, however, until the Second Mexican War, after which the Remembrance historiography sent his reputation into freefall. If Washington was ever painted in a good light, it was in his early years as a soldier fighting French and Indians and British (That he fought the French and Indians under the orders of the British crown is glossed over). His presidency is depicted as an aloof aristocrat taking all the credit for the actions of Adams and Hamilton and Jay. After GWII Washington's reputation is rehabilitated and he's once again considered one of the good presidents, although he never regains his mythic status.
Confederacy: Washington is considered the spiritual ancestor for the CSA from day one - he's on their friggin seal, for crying out loud! Only Jefferson Davis and Robert E. Lee rival him in reputation (until Featherston supplants all three).
John Adams
Union: Adams is usually portrayed as the real reason Washington was so successful. His and Hamilton's attempts to foster better relations with the British are downplayed in favor of his patronage of industry and the navy, and of course showing that rabble-rousers will get the boot stomped on them. Even after GWII, Adams tends to rank in the top 5 presidents.
Confederacy: Confederate historiography considers Adams a footnote at best.
Thomas Jefferson
Union: Yankees are dismissive of Jefferson at best. He's a Virginian slaveholder like Washington, but he's also a Francophile and supporter of decentralized government, so that makes him worse. Most of the credit for the Declaration goes to Franklin, and his intellectual pursuits are habitually ignored. Jefferson tends to be either ignored or vilified, depending on how charitable the historian is feeling. The exception is Missouri, where Jefferson is viewed as something of a founding father to the state.
Confederacy: Jefferson might not be as popular as Washington, but he ranks pretty high, especially in Virginia. To hear a Confederate, Jefferson was solely responsible for everything good that happened in the First Party era that Washington didn't do, and is often painted as Washington's right hand and heir-apparent. His ... relationships are swept under the rug.
James Madison
Union: If there's one president who can rival Blaine in reputation, Madison usually winds up on the short list (har dee har har). From starting a loosing war with Britain (which admittedly was at least partly his fault) to both of his vice presidents dying in office (which ... wasn't, obviously), everything bad that happened in his administration is played up as solely his fault. His work is promoting the Constitution is ignored.
Confederacy: What right-minded Virginian gets into a war with England!?
James Monroe
Union: The Yankees are ambivalent to Monroe. Most of his legacy was undone by secession, so he's been reduced to one of the boring presidents that no one care about.
Confederacy: Monroe tends to be played up as the reason the Confederacy could become a world power - his doctrine was a predecessor to the Confederacy's arguments for intervening in Latin America, and the 1820 compromise allowed the South to thrive even when it was carrying around the North like a stillborn conjoined twin. Also, he had a novel way of dealing with freedmen.
John Quincy Adams
Union: Adams, like his father, is lionized by the North - all blame for 1824 falls squarely on Clay and Crawford for complicating the election. Most of what is written about the first Adams applies to him as well.
Confederacy: Adams, like his father, is habitually ignored by Confederates. Anything good that happened in those four years is attributed to Clay.
Andrew Jackson
Union: He was a Tennessean, but the Yankees, paradoxically, LOVE Jackson. His standing up to the Nullifiers, his licking of the limeys, his founding of the modern Democratic party, what's not to love? IF the Trail of Tears is brought up, the general reaction, especially during the Remembrance era, tends to be "Damn redskins joined the Rebs anyway. So what?"
Confederacy: For the same reasons he's lionized in the North, the South hates Jackson. He has some respect in Tennessee, Louisiana, and Florida, enough that when Featherston came to power his remains were exhumed and reburied in a hidden location so they wouldn't be desecrated, but the Confederates as a whole despise the man who dared defy the great John Calhoun. Sequoyahns aren't fond of him either.
Martin Van Buren
Union: Van Buren tends to be placed high on a lot of lists. Democrats will usually bring up that he was the first president born under the US flag, but Republicans and Socialists will focus on his later work with the Free Soil party and opposition to slavery
Confederacy: As the first openly abolitionist president and Jackson's protégé, Van Buren is probably the most hated antebellum US president in the South. That his free soil views didn't coalesce until after he left office is ignored.
William Henry Harrison
Neither country really has an opinion - his term was too short to judge fairly.
John Tyler
Union: As Van Buren is to the South, so is John Tyler to the North - at least the other Southern presidents had the good sense to die before secession!
Confederacy: After Washington, Jefferson, and Monroe, Tyler is the most respected antebellum president. Texans, especially, love the man.
James K. Polk
Union: Yankees respect Polk, although not to the extent they do Jackson. America was probably the most powerful it'd be until Roosevelt's administration, and that deserves credit. Besides, he made Britain back down.
Confederacy: Polk is probably the only president respected in both countries equally. Confederates tend to downplay Polk's foreign affairs in favor of his heritage, of course.
Zachary Taylor
Union: On the one hand, Taylor was committed to preserving the Union and putting naysayers in their place. On the other hand, he was Jefferson Davis's father-in-law. Maybe if he had lived longer...
Confederacy: On the one hand, he was Jefferson Davis's father-in-law. On the other hand, Taylor was committed to preserving the Union and putting naysayers in their place. Maybe if he had lived longer...
Millard Fillmore, Franklin Pierce, James Buchanan
Both countries agree that these three were pretty bad and constantly made a troubled situation worse.
Abraham Lincoln
Union: For the longest time, Lincoln was viewed as a disaster of president, someone who let good men die over a few slaves. The Republicans and Socialists both respected him, but never really tried to argue in his favor. After GWII, Lincoln, like Washington, begins to experience a rehabilitation, although he still ranks far lower than OTL.
Confederacy: From Davis to Featherston, Lincoln tends to be caricatured as some ape-faced buffoon who stumbles from one military disaster to another. Paradoxically, since the Union lost the War of Secession Lincoln isn't outright hated like his OTL reputation was for the longest time, certainly not to the extent of John Brown or Nat Turner. He's just something of a laughingstock to Southerners.