After receiving rave reviews for his book The Call of the Wild in 1904, Jack London became very enthusiastic about a new idea for a book that would not be a sequel but a "companion" to The Call of the Wild. "I'm going to reverse the process," he wrote to his publisher. "Instead of the devolution of decivilization of a dog, I'm going to give the evolution, the civilization of a dog - development of domesticity, faithfulness; love morality and all the amenities and virtues. With The Call of the Wild as a "forerunner," he declared the new book should "be a hit."
On February 21, 1906 London reported to his editor that he was ready to begin writing White Fang, but on June 7 he had still not started the novel because was "writing some short stories in order to get hold of some immediate cash." He was also busy buying a ranch near Glen Ellen in Sonoma County, California, where his courtship of Charmain Kitteredge flourished. When he finally began writing on June 26, he was happier than he had been in well over a year, and the new novel reflected his belief that the blackest despair could be cured by love. Composition therefore proceeded smoothly throughout the summer until the novel was completed on October 10.
As London planned his account of White Fang's early development, he was particularly careful to adhere to the established facts of the wolf's life cycle. On the basis of an encyclopedia article, he jotted down the following chronology:
"White Fang - is conceived February is born April 3 is blind for 21 days finishes suckling by June 5 had begun to eat meat by May 3 he quits his mother for good in December was full grown in three years lived 15 years"
London wrote White Fang at his characteristic pace, and within five months it was finished and successfully marketed. On November 11 he telegraphed Charmain, "Wild Mate, I have no fancy for dying just yet. White Fang sold." Eight days later Jack and Charmain were married.