Wide Sargasso Sea is a 1966 postcolonial novel by Dominica-born British author Jean Rhys, who had lived in obscurity after her previous work, Good Morning, Midnight, was published in 1939. Wide Sargasso Sea "re-noticed" Rhys, and became her most successful novel.

The novel is a prequel to Charlotte Brontë's famous 1847 novel Jane Eyre. It is the story of Antoinette Cosway, a white Creole heiress, from the time of her youth in the Caribbean to her unhappy marriage to a certain English gentleman—he is never named by the author—who soon renames her, declares her mad and then requires her to relocate to England.