Tom’s last earthly master, the brutal Louisiana plantation owner Simon Legree, is one of the four most famous characters in Uncle Tom’s Cabin – but he doesn’t appear until two-thirds of the way through the novel. Legree’s fame isn’t based on his complexity – it’s hard to imagine a simpler character.
When Legree swaggers into the auction at the slave warehouse, Tom starts shivering immediately, as if he supernaturally senses the man’s evil spirit. And Legree is evil, thoroughly and remorselessly evil. He has no redeeming features. He’s got a conscience, but he’s trampled it under and decided to behave with utterly inhuman cruelty. Once Legree appears, as savvy readers, we know that Tom is doomed.
Whether we quote from Shakespeare or Cake, the point is the same: "I’m gonna be one evil dude." Like the worst villains in Shakespeare’s tragedies (such as Iago in Othello or Edgar in King Lear), Simon Legree is what English major-y people call a "motiveless malignancy." That’s a fancy way of saying that he’s devoted himself to work evil without any real, solid reasons.
There are things Legree cares about: profit, for example, and dominating other people. And he’s a sadist, so he enjoys tormenting other people and swaggering around inspiring fear. But Legree’s abuse of Tom goes beyond any of these motivations. He hates Tom, as the novel says, with "the native antipathy of bad to good" (33.2). Legree and Tom are in conflict largely because Tom is Good and Legree is Evil. Once again, Uncle Tom’s Cabin uses archetypes so much that it’s almost, but not quite, an allegory.
There’s another evil guy that Simon Legree reminds us of, too: Pontius Pilate, the Roman governor who sentenced Jesus to crucifixion. We’ve already described the way that Uncle Tom is a Christ figure (see Tom's "Character Analysis"), so it only makes sense that Tom’s destroyer is similar to Christ’s. Pilate and Legree have the same motivation for murder – getting rid of someone who is stirring up the locals by teaching them the radical idea of universal love. Like Pilate, Legree cross-examines his victim before killing him, but doesn’t get any answers. And again like Pilate, Legree knows that he’s murdering a good man, but finds it expedient to do so.
One of the problems with having Tom’s final antagonist be a "motiveless malignancy" is that it makes him a pretty unrealistic character. In her Key to Uncle Tom’s Cabin, Stowe admitted that only a minority of slave owners could be as thoroughly evil and degenerate as Simon Legree.
The point, however, is that men like Simon Legree could and did exist, and they were largely immune from punishment under American laws. Legree can torture and murder his slaves. He can refuse to let them practice their religion. He can keep them half-starved. He can buy fifteen-year-old Emmeline and use her as a sex slave if he wants. (Stowe doesn’t let him, but as readers we can see how easily it could happen, and how it did happen to Cassy.)
Stowe wants her reader to feel alarmed at even the possibility that someone like Legree could rule men, women, and children with impunity. She shows how the institution of slavery itself could cause even the best of men, like Mr. Shelby and Augustine St. Clare, to slip into sin. And when you have men whose moral nature is coarse, unrefined, and unresponsive to conscience, who are kept unchecked by the law, the cruelty they can perpetuate is terrifying to contemplate. Think of it this way: Stowe’s 19th century reader may be asking, "Well, how bad could slavery possibly be?" Simon Legree is the answer. In other words, unbelievably, horrifyingly bad.
So Legree serves a great moral purpose in the novel: he represents what happens when you give one man total power over another. That man inevitably grows corrupt, perhaps not as corrupt as Legree, but who cares? There are no degrees of corruptness when it comes to owning another person’s body. Legree illustrates that, because genteel society protects the more gentlemanly, kinder forms of slavery, it also protects and allows this kind of slavery.
And Legree serves as a reminder, in Stowe’s words, "that no Southern law requires any test of CHARACTER from the man to whom the absolute power of master is granted" (source). Thus, the answer is to abolish all forms of slavery – not to try to "reform" it. There is no "reforming" a system that allows and perpetuates Legree’s treatment of the men and women he buys.
So far, we’ve explored Legree’s thoroughly degenerate nature and total lack of conscience. But the plot of a novel just can’t work if there isn’t anything at all to keep a character in check or use as a weapon against him. So Stowe gives Simon Legree one big Achilles heel – in fact, it’s more of an Achilles leg. He’s superstitious. He’s afraid of the ghosts of slaves that he tortured to death in his garret. He’s afraid of the ghost of his mother, whose morality and religion he rejected in his youth. And he’s strangely afraid of Cassy’s weird feminine powers. This last is probably the least believable of the three, but Stowe insists on it:
Cassy had always kept over Legree the kind of influence that a strong, impassioned woman can ever keep over the most brutal man; but, of late, she had grown more and more irritable and restless, under the hideous yoke of her servitude, and her irritability, at times, broke out into raving insanity; and this liability made her a sort of object of dread to Legree, who had that superstitious horror of insane persons which is common to coarse and uninstructed minds. (35.14)
If you’re like us, this really doesn’t make a whole lot of sense to you. Legree knows that he has complete power over Cassy; why should he fear her? Since when do "coarse" people always fear insane ones? These are assumptions of the sentimental novel as a genre. One of the underlying ideas of Uncle Tom’s Cabin is that women have a variety of powers in society that they don’t always exercise. Cassy’s particularly female strength – "the kind of influence that a strong, impassioned woman" has – frightens Legree because it’s unknown, and he suspects that it’s incredibly powerful.
There’s also a hint that, because Legree isn’t religious in a good sense, he’s afraid of the afterlife and the metaphysical world:
Ye who have wondered to hear, in that same evangel, that God is love, and that God is a consuming fire, see ye not how, to the soul resolved in evil, perfect love is the most fearful torture, the seal and sentence of the direst despair? (35.36)
So, basically, Legree believes in God and the supernatural, but because he’s allied himself with everything low and base and vicious, he knows that he’s in for it one day.