In early 19th-century Austria the Archduke Rudolph occupied multiple roles: a noble Hapsburg by birth, a Cardinal-Archbishop by career, and a dedicated musician by avocation. A talented pianist and composer, Archduke Rudolph enjoyed the unique privilege of being Beethoven's only composition student, and in the two decades of studying with him produced a sizable and well-crafted body of music for piano, chamber ensemble, and voice. Many of the Archduke's autograph manuscripts were corrected in detail by Beethoven, giving us fascinating insights into Beethoven's thinking on the structure and syntax of music. This comprehensive book surveys Archduke Rudolph's life and career in music, which also encompasses his significant role as music patron and collector. It is based on a study of primary sources, principally the autograph manuscripts of his compositions and sketches, and most importantly, Beethoven's own autographs-including sketches, corrections on the Rudolph manuscripts, and a four-measure theme composed expressly for Rudolph's use-produced here, in facsimile, for the first time. Other primary sources examined include the Archduke's correspondence with Beethoven and members of the Imperial household, the catalogues of Rudolph's music collection, and documents related to his ecclesiastical career. The thematic catalogue of Archduke Rudolph's music lists all of his finished and unfinished works in chronological order, as well as sketches, copies, and transcriptions. Fifty illustrations and 190 musical examples are also provided.