One-Eye is White Fang's father, who doesn't get much screen time here. He's old, sneaky and the final victor in the battle among Kiche's rivals. So we shouldn't be surprised that he does so well in wooing.
If we had to pick his most important quality, we'd say it's his brains Why? Because White Fang definitely inherits some of those smarts, which help him out of more than a few scrapes. Beyond that, he's kind of a barely-there dad: delivering food in the early stages of White Fang's life, then rambling on to find another she-wolf to cozy up to… or, more likely, an eventual messy death at the hands of a lynx. No one ever said life in the Wild was easy.
Lip-lip is another dog in Grey Beaver's camp, and boy does he hate White Fang. He torments him mercilessly, which ends up nudging White Fang along the path to the Dark Side. Or, as our narrator puts it, "Lip-lip continued so to darken his days that White Fang became wickeder and more ferocious than it was his natural right to be" (11.1).
He's basically a warm-up for Beauty Smith, something that White Fang has to deal with, endure and eventually get used to if he wants to survive in the Big Bad World. Unlike Beauty Smith, however, White Fang can handle Lip-lip on his own: after years of torment, the two finally face off in the woods during a famine. There's no greater revenge than being able to eat your tormentor. Or so they say.
Mit-sah is Grey Beaver's son and Kloo-kooch is his wife. They're basically extensions of Grey Beaver, though they're a little kinder to White Fang than he is.
Mit-sah trains White Fang as part of his junior varsity sled team, and finds a sneaky way to get revenge against Lip-lip: "He made Lip-lip the leader, and was apparently an honour! but in reality it took away from him all honour, and instead of being bully and master of the pack, he now found himself hated and persecuted by the pack" (13.5).
Kloo-kooch, even less of a factor than her son, still gives White Fang some food when he returns to their camp: "Kloo-kooch welcomed him with glad cries and the whole of a fresh-caught fish" (14.29). So, she's a nicer, less prominent version of Grey Beaver. Got it.
Judge Scott is Weedon's father who, along with the rest of his household, is pretty skeptical of Weedon bringing a half-crazed fighting wolf into their home. He's the last guy to be won over: "Judge Scott still held to the same opinion, and proved it to everybody's dissatisfaction by measurements and descriptions taken from the encyclopaedia and various works on natural history" (24.37). But you gotta admit that taking down the guy who breaks into your house to kill you is a pretty firm commitment of loyalty. Once Judge Scott is won over, White Fang has basically entered the winner's circle and will surely live happily ever after.
You know that girl in all the movies who just hates-hates-hates a certain guy until they lock lips and confess their undying passion for each other? That's Collie. She makes White Fang's life miserable—but in a playful, non-lethal way—when he first arrives at Scott's place, only to gradually decide that he's actually pretty okay. Soon enough, they're having puppies. She's basically part of his reward at the end of the book—one of his own kind who tolerates and even loves him after life finally gets done beating him up.
Bill and Henry are the mushers in the start of the story, bringing the body of an aristocratic lord back to civilization, and getting chased by wolves for their troubles. Bill is slightly grumpier than Henry, but they're both tough men in tough situations just trying to get out of it with their lives.
Bill may go down, but Henry hangs on long enough for help to arrive. London goes into great detail about his tactics—everything from hoisting the coffin into the trees to building a ring of fire to hold the wolves off. He's rewarded for his ingenuity with survival, which is London's way of setting the tone for the rest of the book while showing us how harsh and merciless the wilderness can be.
Tim is a faro-dealer who owns Cherokee the bulldog, and pits him in mortal combat against White Fang. For a guy who participates in illegal dogfights, he's actually not a totally awful person. He cares about his dog to a certain extent, ominously threatening Scott when it looks like Scott's going to hurt him. Of course, that doesn't excuse the fact that he stuck Cherokee in the ring with a wild animal in the first place, but what are you gonna do?
He's also smart enough not to push Scott too far—no testing of the Alpha male for him—and promptly vanishes once Scott takes White Fang away. He exists mainly as a symbol for human indifference: standing by and letting awful things happen just because he's not inclined to fight about it. He looks after is own interests and no one else's. He's not actively evil, maybe, but he is pretty selfish and ultimately forgettable.
Cherokee's a bulldog who battles White Fang in the ring and almost kills him once he gets his bulldoggy jaws around our hero's throat. He's played mainly as a pawn of mankind. He's not actively vicious and even wags his tail, suggesting some kind of non-traumatic relationship with his master: "Cherokee did not seem anxious to fight. He turned his head and blinked at the men who shouted, at the same time wagging his stump of a tail good-naturedly" (18.3).
He's also patient, waiting for the moment to strike and dealing with White Fang's horrible ninja fang-striking in the process. With Cherokee, London makes an important point about the nature of animals: they're not inherently evil, they only do evil when we ask or make them.
Hall is the escaped convict who enters the Scott home at the very end of the story. He's basically deus ex machina writ large: an evil guy planning to do evil things just to give White Fang someone to disembowel and make for an exciting climax.
But London throws a twist in there. Hall was framed, and while Judge Scott (his intended target) had nothing to do with it, the man got sent up for a crime he didn't commit. His anger is wildly misplaced, but he's a product of his environment: "He had not been born right, and he had not been helped any by the moulding he had received at the hands of society. The hands of society are harsh, and this man was a striking sample of its handiwork" (25.1).
That makes him a little more interesting a character than mere wolf-bait, and also draws a strange connection between him and White Fang. After all, Fang has been treated badly by society, and might have turned out this evil if he'd stayed in Beauty's hands. By killing Hall, he might just be killing that possibility in himself, showing that he is a good dog rather than a canine version of Hall. Nice symbolism there, Mr. London.