Some of 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", "An Odyssey of the North", and "Love of Life". He also wrote of the South Pacific in such stories as "The Pearls of Parlay" and "The Heathen", and of the San Francisco Bay area in The Sea Wolf.
London was part of the radical literary group "The Crowd" in San Francisco and a passionate advocate of unionization, socialism, and the rights of workers. He wrote several powerful works dealing with these topics, such as his dystopian novel The Iron Heel, his non-fiction exposé The People of the Abyss, and The War of the Classes.Jack London's mother, Flora Wellman, was the fifth and youngest child of Pennsylvania Canal builder Marshall Wellman and his first wife, Eleanor Garrett Jones. Marshall Wellman was descended from Thomas Wellman, an early Puritan settler in the Massachusetts Bay Colony.Flora left Ohio and moved to the Pacific coast when her father remarried after her mother died. In San Francisco, Flora worked as a music teacher and spiritualist, claiming to channel the spirit of a Sauk chief, Black Hawk.