xi, 387 p. / A print copy of this title is available through the UO Libraries under the call number: MUSIC MT49 .K36 2006 / The use of basso continuo in the performance of many late eighteenth- and early nineteenth-century genres is well documented, yet the influence of this practice on the Lieder during that time has never been fully explored. This dissertation analyzes Lied accompaniments of the period in relation to the recommendations found in contemporary thorough bass treatises in order to demonstrate that continuo practice did have an effect both on what composers were writing and how the songs were being performed. The majority of written-out Lied accompaniments from the late eighteenth-century conform to the recommendations given by treatise authors on matters of texture, distribution of the notes between the hands, octave doublings, parallel intervals, embellishments, and relationship of the keyboard part to the solo line. Furthermore, figured basses were still printed in some songs into the early part of the nineteenth century. Well-known nineteenth-century Lied composers, such as Schubert, Mendelssohn, and Brahms also frequently use these simple, continuo-like keyboard parts, and incorporate common continuo techniques for filling out chords into their more complex accompaniments. The fact that continuo practice, a tradition in which improvisation played a large role, continued to have such a pervasive influence on the printed Lied suggests that additions and embellishments can be made to what is written on the page. Furthermore, evidence from secondary sources, statements by musicians of the period, and clues in the music itself confirm that composers did not always intend for performers to play exactly what is notated. In this dissertation, I argue that in many of these songs the musical score should be viewed as only a basic outline, which can then be adapted depending on the skill level of the performers, the available keyboard instruments, and the context of the performance. Principles from the continuo treatises serve as a guide for knowing what additions to make, and I offer suggestions of possible applications. Appendices detail the contents of 50 continuo treatises published between 1750 and 1810. / Adviser: Dr. Anne Dhu McLucas Committee: Dr. Marc Vanscheeuwijck, Dr. Marian Smith, Dr. Kenneth Calhoon