This book, first published in 1984, is the third volume of Peter Williams' important reference work, The Organ Music of J. S. Bach. In this volume, Peter Williams lays before the reader the salient points that serve as an appropriate bckground to the pieces: notes on the church services of the area in question (Thuringia - Saxony), the fitful tradition of recitals, the duties of organists, the composer's indebtedness to former and contemporary styles in music, his knowledge of organs, the relevance (often over-valued today) of theorists, details of the instruments he was acquainted with and what can be assumed about the way they were registered and played. Throughout, the author has aimed to present a background to this music and its playing and has avoided stepping into areas of high conjecture, such as chronology or how specific pieces are to be played. This 1984 book is the third volume of Peter Williams' important reference work, The Organ Music of J. S. Bach. Peter Williams (1937–2016) was an internationally renowned Bach scholar and performer. He held the first Chair in Performance Practice in Britain at the University of Edinburgh, where he was Director of the Russell Collection of Harpsichords and latterly Dean of Music. He was also the first Arts and Sciences Distinguished Chair at Duke University, North Carolina. He was the author of many books, including Bach, Handel, Scarlatti 1685–1985 (Cambridge, 1985), The Life of Bach (Cambridge, 2003) and J. S. Bach: A Life in Music (Cambridge, 2007).