Wide Sargasso Sea is a 1966 novel by Dominican-British author Jean Rhys. The novel serves as a postcolonial and feminist prequel to Charlotte Brontë's novel Jane Eyre (1847), describing the background to Mr. Rochester's marriage from the point-of-view of his wife Antoinette Cosway, a Creole heiress. Antoinette Cosway is Rhys's version of Brontë's "madwoman in the attic". Antoinette's story is told from the time of her youth in Jamaica, to her unhappy marriage to an English gentleman, Mr. Rochester, who renames her Bertha, declares her mad, takes her to England, and isolates her from the rest of the world in his mansion. Wide Sargasso Sea explores the power of relationships between men and women and discusses the themes of race, Caribbean history, and assimilation as Antoinette is caught in a white, patriarchal society in which she fully belongs neither to Europe nor to Jamaica.

Jean Rhys, was a British novelist who was born and grew up in the Caribbean island of Dominica. From the age of 16, she mainly resided in England, where she was sent for her education. She is best known for her novel Wide Sargasso Sea (1966), written as a prequel to Charlotte Brontë's Jane Eyre. In 1978, she was appointed a Commander of the Order of the British Empire (CBE) for her writing.