A pioneer in the world of commercial magazine fiction, London was one of the first writers to become a worldwide celebrity and earn a large fortune from writing. He was an innovator in the genre that would later become known as science fiction. His most famous works include "The Call of the Wild" and "White Fang", both set in the Klondike Gold Rush, as well as the short stories "To Build a Fire", and "Love of Life". He wrote about the South Pacific in stories such as "The Pearls of Parlay". He was part of the literary group "The Crowd" in San Francisco and a passionate advocate of unionization, workers' rights, socialism, and eugenics. He wrote several works dealing with these topics.