Well, Mary Shelley, Mrs. Radcliffe, the Final Girl trope, a lot of feminist horror crit as mentioned above by thawrecka. A lot of the golden-age murder-mystery writers were women, and as a kid I saw the mystery and horror genres as adjacent, with equally-gory cover illustrations. Plus I feel like even the mainstream view of horror-as-trash kind of puts it into the same drawer with things like Romance: they’re all Sensation Literature.