William Hope Hodgson (15 November 1877 – 19 April 1918) was an English author. He produced a large body of work, consisting of essays, short fiction, and novels, spanning several overlapping genres including horror, fantastic fiction, and science fiction. Hodgson used his experiences at sea to lend authentic detail to his short horror stories, many of which are set on the ocean, including his series of linked tales forming the "Sargasso Sea Stories". His novels, such as The House on the Borderland (1908) and The Night Land (1912), feature more cosmic themes, but several of his novels also focus on horrors associated with the sea. Early in his writing career Hodgson dedicated effort to poetry, although few of his poems were published during his lifetime. He also attracted some notice as a photographer and achieved renown as a bodybuilder. He died in World War I at age 40.

Hodgson was born in the hamlet of Blackmore End near Braintree in Essex, the son of the Reverend Samuel Hodgson, an Anglican priest, and Lissie Sarah Brown. He was the second of 12 children, three of whom died in infancy. The death of a child is a theme in several of Hodgson's works including the short stories "The Valley of Lost Children", "The Sea-Horses", and "The Searcher of the End House".

Hodgson's father was moved frequently and served 11 different parishes in 21 years, including one in Ardrahan, County Galway, Ireland. This setting was later featured in Hodgson's novel The House on the Borderland.

Hodgson ran away from his boarding school at age 13, in an effort to become a sailor. He was caught and returned to his family, but eventually received his father's permission to be apprenticed as a cabin boy and began a four-year apprenticeship in 1891. Hodgson's father died shortly thereafter, of throat cancer, leaving the family impoverished; while William was away, the family subsisted largely on charity. After his apprenticeship ended in 1895, Hodgson began two years of study in Liverpool and was then able to pass the tests and receive his mate's certificate; he then began several more years as a sailor.

At sea, Hodgson experienced bullying. This led him to begin a programme of personal training. According to Sam Moskowitz,

The primary motivation of his body development was not health, but self-defence. His relatively short height and sensitive, almost beautiful face made him an irresistible target for bullying seamen. When they moved in to pulverize him, they would learn too late that they had come to grips with easily one of the most powerful men, pound for pound, in all England.

The theme of bullying of an apprentice by older seamen, and revenge taken, appeared frequently in his sea stories.

While away at sea, in addition to his exercises with weights and with a punching bag, Hodgson also practised his photography, taking photographs of aurora borealis, cyclones, lightning, sharks, and the maggots that infested the food given to sailors. He also built up a stamp collection, practised his marksmanship while hunting, and kept journals of his experiences at sea. In November 1898, he was awarded the Royal Humane Society medal for heroism for saving another sailor who, in March of the same year, had fallen from the topmast into the sea in shark-infested waters off the coast of New Zealand.