Bertha Mason is a fictional character from the novel Jane Eyre, written by Charlotte Brontë and published in 1847. She is depicted as the first wife of Edward Rochester, the novel's male protagonist. Bertha is often described as having a mysterious and troubled past, which includes her family's history of mental illness. In the story, Bertha is confined to the attic of Thornfield Hall due to her deteriorating mental state. Her presence significantly impacts the plot, as her existence complicates Rochester's relationship with Jane Eyre. Bertha's character raises themes of colonialism, gender, and the treatment of mental illness in the 19th century.