Siegfried Wagner, the son of Richard Wagner and his second wife Cosima, composed fifteen operas in total, expertly written in a late romantic style derived from the influence of Humperdinck. His subjects are generally drawn from medieval German sources, often preoccupied with witchcraft and magic. Der Heidenkönig (The Heathen King), set in the late sixteenth century, deals with the conflict between the forces of Christianity, represented by the Poles, and the old pagan religion of the Wends, and its impact on the lives of the leading characters.