White Fang: is the titular character and protagonist, an animal who is part domesticated dog and part wolf of the Wild, and who experiences a continual struggle between these elements of his character. He is obedient to instincts passed on through countless generations-the instincts not only of his savage wolf ancestors, but also those of his forebears who have submitted to the dominance of men. Yet, in their different ways, both sets of instincts contribute to White Fang's survival. White Fang's journey as a character seems as some times to be shaped mostly by "nature"-his received instincts-and at other times mostly by "nurture"-the treatment he receives from other animals and, most especially, from human beings-but it leads him, and we as readers, to the realization that in order to truly survive-in order to truly live-we must yield to love.
Kiche: is White Fang's mother, a domesticated dog who escaped her Indian master, Gray Beaver, and went off into the Wild for a year. Like her offspring White Fang, Kiche is accountable to two sets of instincts: she survives in the Wild, yet she does so by drawing on her domestic instincts and approaching gold-rushers' fires in order to lure their dogs away to be killed for meat. Kiche also embodies for White Fang the law against dogs attacking the female of their own kind.
Gray Beaver: is the Indian who was Kiche's master, and then becomes White Fang's. He treats White Fang with firm discipline, and administers beatings that seem cruel (albeit less so when compared with those administered by Beauty Smith, q.v.). Nonetheless, he can also be kind toward White Fang, and often is. It is Gray Beaver's combination of (when compared to White Fang) omnipotence and his ability to bestow kindness on the animal that establishes humanity as "gods" in White Fang's mind.
Mit-sah: is Gray Beaver's son, who uses White Fang as the lead dog in his own team of sled dogs. He does not seem to possess his father's understanding of how to combine kindness with discipline, but White Fang must nonetheless submit to Mit-sah as a consequence of his submission to Gray Beaver.
Lip-lip: is another of Gray Beaver's dogs who continually persecutes White Fang. Eventually, however, White Fang kills Lip-lip. The incident confirms both White Fang's dominance and Lip-lip's contribution in making White Fang the ferocious beast that he is. Lip-lip thus represents one of the ingredients that make up White Fang's "nurture" in the novel, and is, in a sense, the parallel in the animal world to Beauty Smith (q.v., for Beauty Smith complicates the question of who is a civilized animal and who is not).
Beauty Smith: is the ironically nicknamed gold-rusher and trader who purchases White Fang from Gray Beaver by addicting the latter to alcohol and then offering him bottles of whiskey in return for the animal. Beauty Smith is by far a harsher master than Gray Beaver ever was. He beats and abuses White Fang terribly, and-perhaps worst of all, considering White Fang's ferocity of spirit, the indomitable power of the life force that is in him-he laughs in mockery at White Fang. The sum effect of this "nurture" is to make White Fang more ferocious and wilder than ever, in order that he can win Beauty Smith money in dog fights. Although Beauty Smith is a thoroughly disagreeable character, the narrator insists that, like White Fang, Smith, too, is a product of his environment. The raw "clay" of his life has been molded no less than has the wolf-dog's by circumstances beyond his control. Nonetheless, most readers cannot bring themselves to absolve Beauty Smith completely-which in itself may be London's way of showing the limits of the perennial "nurture versus nature" debate.
Weedon Scott: is called "the love-master" in the text, and that moniker aptly describes his relationship to White Fang. Weedon Scott gives White Fang the only pure experience of love the animal knows. He is a gentle man who "redeems" White Fang from his miserable existence with Beauty Smith and who, by patient tenderness, allows White Fang to feel and respond to love-and, in turn, to love back.
Collie: is a sheepdog owned by the Scott family at Sierra Vista who responds to White Fang's arrival at the house with initial distrust and hatred-for she, too, is responding to instinct, the inbred instinct of previous generations of sheepdogs who viewed wolves as the enemy-but who eventually lures White Fang into the woods to mate. The relationship between Collie and White Fang points to the persistence of life. Their act of love creates the possibility of future life.
Judge Scott: is Weedon Scott's father. He is dubious that his son will be able to "civilize" White Fang, but Weedon-and White Fang himself, of course-ultimately prove the judge wrong. When White Fang can be in the chicken yard without killing the birds, Judge Scott, true to his previous promise, tells him very solemnly and repeatedly, "White Fang, you are smarter than I thought."
Jim Hall: is a hardened criminal whom Judge Scott sentenced-unwittingly, as part of a larger government and law enforcement conspiracy against the man-to fifty years in prison. Readers are told that Hall, like Beauty Smith, is a product of a hard upbringing, a "defective nuture" (not London's phrase). He escapes from prison and goes to the Scott home to take revenge on Judge Scott, only to be stopped and killed by White Fang.