Luke Skywalker: Ravenclaw. While Luke has some traits of every house, his inner journey is essentially the journey of a young boy searching for truth. Having spent his whole life on his aunt and uncle’s farm, he gazes at the horizon, dreaming about what’s out there beyond the two suns of his home planet. While this could be interpreted as a Gryffindor quality, a longing for adventure and heroism, remember how reluctant he was at first to get involved with the Rebellion. I think it must have been more of a longing to see and experience something beyond the limited, monotonous world he was raised in. To discover that “bright center of the universe” he believes Tattooine is farthest from. His inner growth throughout the three movies is all about learning, about gaining knowledge and wisdom, and about uncovering secrets that have been hidden from him. Luke agrees to let Obi-Wan teach him to be a Jedi, and later leaves the Rebellion to find Yoda and continue his training, so this is clearly something that is important to him. He even puts up with Yoda’s criticisms and frustrating idiosyncrasies because he believes that he can learn something from the strange old creature. When he discovers that Darth Vader is his father, he seems to care less that his father is someone so horrible and more that his two most trusted mentor figures lied to him. In the end, he becomes an intelligent, intuitive young man who trusts his instincts and is wise enough not to fall for the Emperor’s manipulations. He pieces together his own, more complete version of the truth from the many different “certain points of view” he is given, and he emerges with a balanced view of the world that cannot easily be corrupted.
Leia Organa: Gryffindor. Far from being a damsel in distress, Leia is a fiery warrior princess. Like many Gryffindors, she believes strongly in her cause and is willing to die for it if necessary. She stands up to her captors in A New Hope and refuses to betray the location of the rebel base even under implied torture and extreme emotional manipulation. She’s more than capable of holding her own in battle, although her role in the Rebellion seems to be more political and she takes part in only a few of the large-scale fights. There are moments when Leia’s strategic side shows and she reveals a Ravenclaw or even Slytherin edge, a leader who can put her own feelings aside. For instance, locking Luke and Han out of the rebel base on Hoth was not exactly a Gryffindor move, and I don’t mean that it was cowardly. I just mean that it’s a logical, strategic decision that was necessary to keep the rest of the Rebels safe, not an emotion-driven, rush-into-danger-impulsively Gryffindor choice. However, even here, her motivation is her loyalty to her cause, and her decision is a selfless one. On the whole, she’s a bold, brave Gryffindor who will fight tooth and nail for what she believes in.
Han Solo: Slytherin. Ironically, in the situation on Hoth that I mentioned above, Han is the one doing the Gryffindor thing, rushing into danger to try to save a close friend. However, there are very, very few people he would be willing to do that for, and the fact that he does so for Luke shows just how much he respects and cares for him. Han’s whole modus operendi is to look out for himself first, and Luke, Leia, and Chewbacca are unique in that they’re just about the only exceptions to that rule. Even when he joins the rebellion, it’s more about him being there for them than about him suddenly becoming a selfless and idealistic Gryffindor or a loyal, hard-working Hufflepuff.
Obi-Wan Kenobi: Hufflepuff. It would be so easy to call him a Ravenclaw just by virtue of the wise old mentor archetype, but then again, Dumbledore himself was one of those, and he was a Gryffindor. Obi-Wan values loyalty more than truth or knowledge. He sees missing data from the Jedi archives as simply an inconvenience to his mission, whereas a Ravenclaw would have been morally outraged at the thought of important information being covered up. Likewise, he plays his own part in covering up information when he tells Luke that Darth Vader killed his father. He easily rejects personal attachments in favor of loyalty to the Jedi as a whole and accepts their Code without ever really questioning it. He begs Yoda not to make him face his former friend and apprentice, but when he is ordered to, he goes through with it despite his reluctance, stopping just short of killing Vader. Many years later, he serenely sacrifices his own life for the greater good and makes plans for Yoda to continue Luke’s training. He sees himself as a piece of something greater than himself, and he is driven by loyalty and duty above all else.
Darth Vader/Anakin Skywalker: Gryffindor. Darth Vader may be the villain, but he has very few Slytherin traits. For one thing, he has almost no ambition. While his younger self gave lip service to becoming “greater than any Jedi”, that power he’s craving is not the kind he ends up with under the Empire. He seems more focused on being able to decide how to live his own life, love who he loves without having to hide it, and protect the people he is closest to from dying. Those are not really Slytherin goals. He’s not particularly cunning, either. It’s the Emperor who comes up with all the grand schemes, in which Darth Vader is really little more than a pawn. As a young man, he had little patience with the diplomacy and negotiation that Padme insisted was necessary to democracy. He doesn’t think through his actions, and he doesn’t really stand for anything, which is why he’s so easily drawn into the Dark Side. But impulsive heroics and a deep-seated need to save everybody are Gryffindor traits, ones that can be seen in Harry himself, even if in this case they are tragic flaws that lead to his downfall. My only hesitation is that Gryffindors usually have some kind of guiding beliefs or moral compass; however, this the one Gryffindor villain from the Harry Potter books is likewise lacking in this, and that is what leads him to the Dark Side as well. At least, unlike Peter Pettigrew, Darth Vader retains his bravery and impulsive nature after his fall from grace.
Padme Amidala: Hufflepuff. Probably the most difficult character to sort, Padme is a bit of everything. She’s intelligent, but her priorities are not centered around knowledge, truth, or wisdom. She’s strategic, but only in a selfless, ideal-driven way, much like Leia. She’s courageous, but she prefers to find a diplomatic solution rather than fight it out on a battlefield. I think her strongest trait is her loyalty: to the people who elected her, to the Republic in general, to the idea of democracy, and to her boyfriend/husband. It’s when these loyalties come into conflict that she is undone.
Yoda: Slytherin. Not for ambition, but for cunning. Yoda is nothing if not cunning. While he’s certainly wise and intelligent enough to be a Ravenclaw, he’s also very pragmatic. For one thing, he’s able to separate himself completely from emotions and personal affections, making decisions purely based on logic. While this is a Jedi thing in general, it comes far more easily to him than to anyone else, even the loyal Hufflepuff Obi-Wan. He’s also good at telling people exactly what they need to hear so that they will do what he wants; for example, he does not tell Luke the true identity of his father so that it will be easier for him to fight and kill Darth Vader. He’s clever enough to trick and test Luke when they first meet, convincing him that he is only an ordinary swamp-dwelling creature agreeing to take him to Yoda before revealing his true identity. And while he’s not driven by ambition, he has no problem with the suggestion that the Jedi take control of the Senate after getting rid of Palpatine.
Emperor Palpatine: Slytherin. Of the very worst kind: power-hungry, ruthless, and manipulative. I’m not sure what else there is to say here. There’s not a single thing he does that isn’t 100% pure Slytherin villainy.