Though an acknowledged constituent part of 18th century musical life, no satisfactory collective study of the composing aristocrat in that era has hitherto been undertaken. The primary aim of this thesis is to identify as many dilettante aristocratic composers as possible, to establish how much of their output has survived, and where - especially in the case of manuscript survivals - the source material is housed. Postwar relocation, war loss and damage, as well as simple error in existing works of reference, have made the locating of source material in sane cases problematic, and the present study has been able to up-date sane of the information given elsewhere. Without entering into debate as to the qualitative aspects of much of the musi...