German musicologist whose works on music harmony are considered to have been the foundation of modern music theory.

Riemann's early musical training was in piano and theory, and he later studied law, philosophy, and history before returning to his musical studies at the Leipzig Conservatory. Riemann obtained his Ph.D. at Göttingen in 1873 and was then active as a conductor and teacher at Bielefeld until 1878, when he became a lecturer on music at the University of Leipzig. During 1880–81 he taught at Bromberg, then at the Hamburg Conservatory until 1890. He returned to the Sondershausen Conservatory for a short time, then taught at the Wiesbaden Conservatory until 1895, when he resumed his lectures at Leipzig. In 1905 he was made a full professor there and three years later he was appointed director of the newly organized Collegium Musicum, a musicological institute created by him. In 1914 he also founded and became the director of the Forschungsinstitut für Musikwissenschaft.

Riemann's immense output covers every aspect of musical scholarship and is a monument to his enormous intellect. He is perhaps best known for his Musiklexikon (1882), which was reprinted in many subsequent editions.