Final answer:
Wagner's early operas were predominantly based on Norse mythology, reflecting his innovative operatic approach that included the use of an orchestra pit.
Step-by-step explanation:
Richard Wagner, the renowned German composer famous for his operatic innovations, based his early operas predominantly on Norse mythology. Wagner's revolutionary approach to opera included thematic elements derived from ancient myths, as well as his introduction of the orchestra pit which served to heighten the dramatic effect of the music, making it a 'magical' support for the action on stage.
His artistic progressiveness can be seen as part of a tradition stretching back to ancient Greek theater, where playwrights pondered philosophical questions and used music and dance to enhance their stories.