Click to read my introduction to this series, Part 1, and Part 2.
From 1963's The Sword in the Stone, we are moving on just a couple of years or so to 1967's The Jungle Book. This film is a bit like 1951's Alice in Wonderland in the sense that Mowgli, like Alice, is essentially just wandering around a land and meeting different types of characters--but Mowgli does have more characterization than Alice does, so we have at least enough of a sense of who he is for this post.
The obvious trait to bring up, though, doesn't have to do with Mowgli's character but rather with his physical self. The story takes place in India, meaning that Mowgli's the first non-white character in this series, even though we're still in the sixties. It took until the nineties for the Disney princesses to start gaining some racial diversity. So that's cool that the boys got a head start in this area (interestingly, I count both five non-white characters in this series and in the princess series).
Like Pinocchio and Arthur, Mowgli is just a boy, not a teenager like the princesses are. Like Aurora, though, he grew up outside of "his" homeland and within Nature. Instead of being raised by fairies, though, he's raised by wolves. The thing is, though, The Jungle Book turns everything around: instead of Mowgli's upbringing being evidence of wildness, it is evidence of innocence. He is raised to respect Nature and the animals within it, rather than loving hunting and guns like Man (when raised among his own kind) does.
Mowgli, then, is a completely positive character. Just look at him interacting with the other animals, for instance. He observes them and sees how they do things and then joins in. He's friendly and interested in learning others' ways. He talks to the young elephant before joining in the elephant march. He quickly starts up a mentor/apprentice relationship with Baloo. Near the end of the film, when he is feeling sad and betrayed, the vultures, by acting friendly to him, remind Mowgli of who he is: a friend to everyone who accepts him.
The reason Mowgli is so friendly with so many different types of animals is that he sees what they all have to offer. When Bagheera comments on Mowgli's ineptitude at climbing a large tree, Mowgli explains that it's because he doesn't have claws like Bagheera does. He's smart, and he's able to recognize individual strengths--and to try and imitate any strengths that he sees.
Mowgli is brave, too. Because the jungle is the only home he's ever known, he stands up to Bagheera and says that he wants to stay and isn't afraid of Shere Khan. This isn't just words, either. When he does finally face Shere Khan, Mowgli doesn't run: he prepares to fight instead. And when the vultures try and get him away to safety, he protests, "Let go--Baloo needs help." He won't flee just to save himself when he knows his friend is in danger.
Not that Mowgli is entirely without fault. He does fall for King Louie's offer. But he also learns from misjudgments. The second time Kaa tries to get him, Mowgli knows what's happening and knows not to trust Kaa. And Mowgli is, after all, just a child, so it's natural (well, it would be at any age, too, honestly) for him to misjudge some situations.
It's the princesses who are known for making friends with animals, but Mowgli quite literally talks to and befriends animals--and not in the casual way of Snow White or Aurora. He talks with them and shares in their stories and gets to know them, so much so that they are willing to risk their lives to save him. That makes Mowgli, first and foremost, a friend, which is not a bad trait at all.