The circumstances surrounding the compilation of many seventeenth-century English keyboard manuscripts remain unknown. The most concrete information exists for the early-seventeenth-century repertory, and scholars have also identified several copyists from sources dating from the end of the century. Without considering the question of repertory, the focus on the earlier manuscripts can be explained in part for the following reasons. A few volumes are associated in some way or another with famous composers (for example, Thomas Tomkins and his autograph Conservatoire National de Musique (in Bibliothèque Nationale), Paris, (F-Pc) MS Rés. 1122), and others are noteworthy for their expansive contents (Fitzwilham Museum, Cambridge MS Mu 128, the famous ‘Fitzwilliam Virginal Book‘). Others are well known because their copyists are familiar personalities, such as British Library, London (Lbl) RM MS 23.1.4 and F-Pc MS Rés. 1185—both connected with Benjamin Cosyn, organist of Dulwich College and conspicuous for his knowledge of John Bull's music. However, the copyists of most mid-century keyboard manuscripts remain unidentified. Concrete information concerning the copyists of a few sources exists, but most identified copyists are unknown men or women—keyboard music in the hand of a prominent musician is quite rare.