The Old Hall Manuscript (British Library, Add MS 57950) is the largest, most complete, and most significant source of English sacred music of the late 14th and early 15th centuries, and as such represents the best source for late Medieval English music. The manuscript somehow survived the Reformation, and formerly belonged to St. Edmund's College, a Roman Catholic school located at Old Hall Green (hence its name) in Hertfordshire. It was sold to the British Library after an auction at Sotheby's in 1973.[1]