That being said, the movie still looks, feels, and sounds like Disney animated classic, which is not a bad thing at all. While it's obviously a children's movie, it doesn't pull too many punches. While both Hols and Arthur from the Disney movie "The Sword in the Stone" get their magic weapons in the same way, Prince of the Sun isn't all kids' stuff. The opening sequence is actually a pretty taut action sequence: Hols, the courageous Norse hero, defends himself from a pack of evil wolves with an axe on a rope. It's very well-choreographed and animated, but doesn't manage to be too violent, or gruesome in any way. Not only that, but the antagonist, Grunwald, wants to rule the world by killing off the human race, which has been forced into a tiny fishing village on a northern fjord. Some of the themes of the movie, like Socialism and xenophobia might be lost on children too.
Another Disney-like quality of Prince of the Sun is the music, it's damned great. The soundtrack has a beautiful and rousing score, and most of the background music follows the motif of the awesome main theme, which basically sings about how awesome Horus is. There's some more singing later on in the movie, but it's not obtrusive and fits the scenes rather well. You won't have to worry about a spontaneous dance number, but the singing that's there is rather beautiful, if mournful at times.
And like any good Disney film, the movie looks gorgeous. While they don't have the same detail as say, a modern Chibli movie, they're still very pretty, and make the movie even more worthwhile. According to the wikipedia, it was behind schedule, and over 30 minute of film had to be cut, and replaced with still images. It's a bit jarring to go from fluid-looking movement to still frames, but it doesn't happen too often, and the rest of the visuals make up for it. The characters have this soft, rounded look to them, but that doesn't make Horus look any less the hero, and some of the enemies he faces, like a giant fish monster with a death beam would probably be nightmare fuel for a little kid. Speaking of Horus, he makes the movie. He has the qualities of any good shonen hero, but with more resolve, and less stupidity.
I'd say that even if you're not a fan of older anime, you'll be enchanted by Prince of the Sun. It made me feel all fuzzy and nostalgic inside, and I can easily see my younger self falling in love with it, and scrambling over the couches with a toy axe to imitate Horus' heroics. If I'm ever dumb enough to have children, I'll be certain to show them this film. It's a piece of anime history, and a great one at that. I totally recommend it.
