Where does the novel The Madwoman in the Attic take place?

The Madwoman in the Attic is not a novel, but instead a feminist study of a collection of nineteenth-century British novels which are quintessential of the Victorian period. 
The authors, Susan Gubar and Sandra M. Gilbert, are both professors in the fields of Women's Studies and feminist studies. The novel was published in 1979, at the tail-end of second-wave feminism. 
The book takes its inspiration from Charlotte Bronte's Jane Eyre. In that novel, Jane encounters Bertha Mason Rochester, the first wife of her employer, Edward Rochester. In Bronte's novel, Bertha is mysterious, crazy, and a burden. Jane is her foil: sweet, orderly, and dutiful. If Jane is the "angel" of the Rochester estate, then Bertha is the "monster," based on the dichotomy created by Gubar and Gilbert. This metaphor coincides with the notion of "the angel in the house," an idea of ideal femininity taken from the title of a poem by Victorian poet Coventry Patmore.
Other authors explored in The Madwoman in the Attic include Emily Bronte, Jane Austen, Mary Shelley, George Eliot, Elizabeth Barrett Browning, Christina Rossetti, and Emily Dickinson. As disparate as this medley of poets and authors is, they all deal with common themes in their work: domesticity, the expectations for middle-class women, romance, and, in the cases of Shelley and Rossetti, aspects of the grotesque and Gothic, a theme that was once also explored by Austen in Northanger Abbey.