J. S. Bach composed some of the best-loved and most moving music in Western culture. Surviving mostly in manuscript collections, his music also exists in special and unique publications that reveal much about his life and thoughts as a composer. In this book, Peter Williams, author of the acclaimed J. S. Bach: A Life in Music, revisits Bach's biography through the lens of his music. Reviewing all of Bach's music chronologically, Williams discusses the music collection by collection to reveal the development of Bach's interests and priorities. While a great deal has been written about the composer's vocal works, Williams gives the keyboard music its proper emphasis, revealing it as crucial to Bach's biography, as a young organist and a mature composer, as a performer in public and teacher in private, and as a profound thinker in the language of music.