"The first volume of [Spitta]'s epoch-making study of Bach appeared in 1873; two years later he was appointed professor of music history at the University of Berlin and administrative director of the Berlin Hochschule für Musik, positions he held until his death. Spitta's approach in the Bach biography reflected the traditional concept of art history as the history of individual artists, but was tempered with a strong, fresh emphasis on historical context. The introductory chapters, for example, present the first detailed study of 17th-century German choral and keyboard music. In subsequent works his concern became increasingly the refinement of musicological research. By his rigorous application of source-critical studies (his aesthetic judgments were strongly influenced by neo-Kantian philosophy), he laid the foundations of a system of historical criticism. He was exceptionally active and productive as a researcher, teacher, writer and editor, and he developed an interest in almost every period of music history, from the early Middle Ages to the music of his own time." (Christoph Wolff, Grove Online.)