John Barleycorn is an autobiographical novel by Jack London dealing with his enjoyment of drinking and struggles with alcoholism. It was published in 1913. The title is taken from the British folksong "John Barleycorn".In this memoir, there are the themes of masculinity and male friendship. London discusses various life experiences he has had with alcohol, and at widely different stages in his life. Key stages are his late teen years when he earned money as a sailor and later in life when he was a wealthy, successful writer.

Jack London (born John Griffith Chaney, January 12, 1876 – November 22, 1917) was an American author, journalist, and social activist. He was a pioneer in the then-burgeoning world of commercial magazine fiction and was one of the first fiction writers to obtain worldwide celebrity and a large fortune from his fiction alone. Some of his most famous works include The Call of the Wild and White Fang, both set in the Klondike Gold Rush. 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 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.