The setting of the story

 

The setting is one of the key factors that help us understand this story.  “To Build a Fire” is set in the Klondike in the Yukon Territory of Canada, the site of a gold rush in the late nineteenth century. The terrain is rugged, and the weather is harsh. Winter lasts seven months, most of them sunless. After gold was discovered there, the region was overrun with thousands of people in search of instant fortune. This fact makes us guess that the character of the story was one of them.

The weather conditions are really severe. It is more than 50 degrees below zero -  “the tremendous cold”. The readers can imagine the sensations one experiences in such conditions due to London’s detailed description of the cold wind and the ice crusting over the man's face: "The man's red beard and moustache were likewise frosted, but more solidly, the deposit taking the form of ice and increasing with every warm, moist breath he exhaled. Also, the man was chewing tobacco, and the muzzle of ice held his lips so rigidly that he was unable to clear his chin when he expelled the juice".  Throughout the story the descriptions like this make you feel the chill of the air, and make you bend your fingers to check whether they are not numb and frozen and you can still use them.

Moreover, the surrounding is not only dangerous but really treacherous. There are traps in form of hidden spring pools, snow can at any moment fall from branches of spruces and blot your fire out. London places his character  in a harsh natural setting that tests his ability to survive in the wilderness. Thus, the story has a philosophical aspect.  It should make us "meditate upon [our] frailty as a creature of temperature, and upon man's frailty in general, able only to live within certain limits of heat and cold" and eventually take us into "the conjectural field of immortality and man's place in the universe".

 At the end of the story the man realizes how stupid of him was to ignore the old-timer’s advice “that no man must travel alone in the Klondike after fifty below”. Once again we understand that very often people cannot survive on their own. We can’t always rely only on ourselves. People need to stick together.