This thesis provides the first detailed examination of the output of the British composer, Denis ApIvor (b. 1916), encompassing what may be described as the formative period of his development, 1933-62. The primary intention is to demonstrate that extra-musical influences -- namely poems, ballet scenarios, opera libretti and visual sources -- have provided the framework for the various stylistic positions which have been adopted by the composer during this period.
The first two chapters are concerned with ApIvor's early career to 1939 and the salient aspects of his almost exclusively song-based output. Chapter 3 discusses the composer's first substantial work, his choral-orchestral setting of T. S. Eliot's The Hollow Men. Chapter 4 discusses by way of an interlude, the compositions of the war and immediate post-war years, culminating in a consideration of the factors which led to ApIvor's decision to commit to serialism in 1948. Chapter 5 examines the ways in which ApIvor's second Eliot setting, Landscapes, provided a vehicle for his early experiments with serialism. Chapter 6 discusses the effect of the theatre works of the 1950s on the composer's serially-derived language, through a consideration of three ballets, A Mirror for Witches, Blood Wedding and Saudades, and the opera Yerma. Chapters 7 and 8 are concerned respectively with the composer's experiments in the post-Webern idiom and its subsequent application in two orchestral works based upon extra-musical sources, the Cantata on Texts of Dylan Thomas and Overtones, after pictures of Paul Klee.
The conclusion is in two parts. The first considers the general characteristics of ApIvor's remaining output between 1962-96 in order to provide pointers for future research. The second places the observations that have been made during the course of the study in the context of the national, spiritual and emotional peculiarities of ApIvor's outlook.