Joseph Frederick Wagner (born April 12, 1863 – died March 9, 1910) was an influential American composer and conductor, notable for his contributions to the early 20th-century American music scene. Although primarily recognized for his work in the light opera and musical theater genres, his compositions also spanned into orchestral and choral music. Wagner's most significant works include "The King of the Golden River," a light opera that showcased his ability to blend narrative with melodic charm, and various operettas that gained popularity in the United States during his lifetime. His compositions often featured lush harmonies and engaging rhythms, reflecting the transitional style of American music at the turn of the century. Wagner's impact on music is seen in his role as a bridge between European operatic traditions and the burgeoning American musical theater landscape. He contributed to the development of a distinctly American voice in music, influencing future generations of composers in the realms of musical theater and operetta. His work is a testament to the cultural evolution of American music during a period of significant change and innovation.