Krakauer himself was part of the expedition that was caught in the blizzard on Everest in 1996, and his book is a first-hand account of his experiences. However, he decided to include a fictional character, Cap Cicero, as a way to explore the psychological and philosophical questions surrounding the dangers and motivations of climbing Everest.
While Cap Cicero is not a real person, Krakauer's book has been very influential in raising awareness about the risks of climbing Everest, as well as the complex relationship between humans and nature.