When classifying the Disney villains, most appeared Caucasian in appearance with the exception of Jafar from Aladdin and Dr. Faciliar from The Princess and the Frog. In Mulan, Shan-Yu is technically Mongolian whereas Mulan is Chinese, but both have stereotypically Asian features. In these three instances, the races and skin colors of the villains and heros are defined by their cultural context, but can further be broken down into their differences between hero and villain.
The clearest example of a villain with darker skin is in Mulan where Shan-Yu has much darker skin than Mulan that looks more gray than anything. This makes the Mongolians seem subhuman and subtly reinforces the idea that darker skin is more evil.
Another, more subtle and controversial example is seen in Aladdin. Although it is often pointed out that Jafar has darker skin than Jasmine, the color differences in most frames of the film are slight. Jafar’s skin almost looks lighter than Jasmine’s in this still image taken directly from the film.
The most notable example of Jafar’s darker skin is in the infamous kissing image. It’s hard to determine why Jafar’s skin changes so much throughout the film, but perhaps he was given a different and more noticeably different skin color in this frame to differentiate between them when they were so close together.
One counterexample of the “darker is evil” hypothesis is seen in Princess and the Frog. Dr. Facilier is actually no darker than Tiana. This is true in both the film itself and its promotional materials. In fact, in the still below, Tiana actually looks a bit darker than Facilier.
Perhaps Disney was more cognizant of issues about skin color when making Princess and the Frog and realized that making Dr. Facilier’s skin darker was unnecessary and offensive, especially to the African Americans to whom Disney was strongly marketing the film. Hopefully this shows signs of progress and that Disney is putting more thought into the racial messages it is sending children over what is good and evil.