The musical compositions of Frederick Delius (1862âÂÂ1934) cover numerous genres, in a style that developed from the early influences of composers such as Edvard Grieg and Richard Wagner into a voice that was uniquely Delius's. He began serious composition at a relatively advanced age (his earliest songs date to his early twenties), and his music was largely unknown and unperformed until the early 20th century. It was a further ten years before his work was generally accepted in concert halls, and then more often in Europe than in his home country, England. Ill-health caused him to give up composition in the early 1920s and he was silent for several years, before the services of a devoted amanuensis, Eric Fenby, enabled Delius to resume composing in 1928. The Delius-Fenby combination led to several notable late works.
The "principal" works are those identified as such by Eric Fenby. A division of Delius's work into phases such as "apprentice" and "middle period" has been suggested by many commentators, notably Anthony Payne in "Delius's Stylistic Development" (1962).
A definitive catalogue of the works of Delius was produced by Robert Threlfall in 1977, and a supplement to it in 1986. It is abbreviated as RT. The Threlfall sectioning is a categorization where works are assigned nominal numbers according to a roman-numeric genre numbering scheme. For example, A Village Romeo and Juliet is, according to Threlfall's counting, the sixth piece of dramatic work Delius composed. Thus, the piece is in Section I, number 6, so is designated RT I/6.