The Call of the Wild, published in 1903, remains London’s most famous work, blending his experiences as a gold prospector in the Canadian wilderness with his ideas about nature and the struggle for existence. He drew these ideas from various influential figures, including Charles Darwin, an English naturalist credited with -developing theories about biological evolution, and Friedrich Nietzsche, a prominent German philosopher. Although The Call of the Wild is first and foremost a story about a dog, it displays a -philosophical depth absent in most animal adventures.

London was married twice—once in 1900, to his math tutor and friend Bess Maddern, and again in 1905, to his secretary Charmian Kittredge, whom he considered his true love. As his works soared in popularity, he became a contradictory figure, arguing for socialist principles and women’s rights even as he himself lived a materialist life of luxury, sailing the world in his boat, the Snark, and running a large ranch in northern California. Meanwhile, he preached -equality and the brotherhood of man, even as novels like The Call of the Wild celebrated violence, power, and brute force.