Final answer:
Wagner's operas drew on mythology, legend, and historical sources, and he innovated in theater design with the introduction of the orchestra pit to enhance the performance's magic.
Step-by-step explanation:
Richard Wagner, the German composer, used various materials for the storylines of his operas. Wagner was known for drawing inspiration from a wide range of sources, including mythology, legends, historical events, and literature. For example, his opera 'Tristan und Isolde' is based on a medieval romance, while 'Die Meistersinger von Nürnberg' is set in the world of German guilds. Wagner also created original stories, such as his epic 'Ring Cycle' which combines elements of Norse mythology and German folklore.
The storylines for Richard Wagner's operas often drew upon mythology and legend, germanic folklore, epic narratives, and historical sources, as seen in operas like 'Der Ring des Nibelungen' which is based on Nordic and Germanic legends, and 'Parsifal' which draws from Arthurian legend. In creating his operas, Wagner was known for pushing the boundaries of acceptability in his day, much like other composers such as Berlioz and Strauss. His innovative ideas extended to theater design as well, which led to the creation of the orchestra pit - a design feature that allowed music to support the action on stage without the source being visible to the audience, thereby enhancing the magical ambiance of the performance.