"Die Ahnfrau" is a one-act opera composed by Hermann Goetz in 1894. The story is based on a play by Franz Grillparzer and revolves around themes of love, betrayal, and the supernatural. It features a young nobleman, Hermann, who is haunted by the ghost of his ancestor, the Ahnfrau, as he grapples with his feelings for Marie and the consequences of his family's past. The opera is set in a mystical landscape, blending elements of folklore and drama. It explores the tension between duty and desire, as well as the impact of ancestral legacies on the present. "Die Ahnfrau" is notable for its rich orchestration and emotional depth, making it a significant work in the late Romantic opera repertoire.