Antoinette Cosway

Bertha Antoinetta Mason is a fictional character. In Charlotte Brontë's 1847 novel Jane Eyre she is the violently insane first wife of Edward Rochester, moved to Thornfield Hall and locked in the attic.

The 1966 parallel novel Wide Sargasso Sea by Jean Rhys acts as a prequel to Brontë's novel and is the story of Mason (there called Antoinette Cosway), from the time of her youth in the Caribbean to her unhappy marriage and relocation to England. Rhys's novel re-imagines Brontë's devilish madwoman in the attic.

Bertha Mason is the only daughter of a very wealthy family living in Spanish Town, Jamaica. The reader learns of her past not from her perspective but only through the description of her unhappy husband, Edward Rochester. She is described as being of Creole heritage. According to Rochester, Bertha was famous for her beauty: she was the pride of the town and sought after by many suitors. Upon leaving college, Rochester was persuaded by his father to visit the Mason family and court Bertha. As he tells it, he first met her at a ball she attended with her father and brother Richard, where he was entranced by her loveliness. Despite never being alone with her, and supposedly having had scarcely any interaction or conversation with her, he married her for her wealth and beauty, and with fierce encouragement from his own father and the Mason family. Rochester and Bertha began their lives as husband and wife in Jamaica. In recounting the history of their relationship, Rochester claims, "I thought I loved her. . . . Her relatives encouraged me; competitors piqued me; she allured me: a marriage was achieved almost before I knew where I was. Oh, I have no respect for myself when I think of that act! . . . I never loved, I never esteemed, I did not even know her."

Rochester explains that he was not warned that violent insanity and intellectual disability ran in the Mason family and that the past three generations succumbed to it. He assumed Bertha's mother to be dead and was never told otherwise, but she was in fact locked away in an asylum. Bertha also had an intellectually disabled younger brother. Rochester's father knew of this but did not bother to tell his son, caring only about the vast fortune the marriage would bring him, and the Mason family clearly wanted Bertha off their hands as quickly as possible. Rochester asserts that Bertha's mental health deteriorated quickly, though it is unclear which form of mental illness she suffers from. Her insane, violent behaviour becomes frightening to behold. She crawls on all fours, snarling, and behaving in a bestial manner.

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