His wife, Paula, is a vivacious, athletic, and sexually self-aware woman, who falls in love with Evan Graham, an old friend of her husband.

Biographer Clarice Stasz writes that the book is "not autobiography", but speaks of London's "frank borrowing from his life with Charmian", his second wife, and says it is "psychologically valid as a mirror of events during [the] winter [of 1912–13]".

Based on a reading of Charmian's diary, Stasz identifies Evan Graham with two real-life men named Laurie Smith and Allan Dunn.

[1][page needed] Even minor characters can be identified; Forrest's servant Oh My resembles London's valet Nakata.

The long-bearded hobo philosopher Aaron Hancock resembles Frank Strawn-Hamilton, who was a long-term guest at the London ranch.