Daniel Jenkyn Jones is often regarded as having been the greatest Welsh composer. His music is marked by traditional form, some adherence to tonality, and complex meters. His most notable works are his 13 symphonies (in 12 different keys) and eight string quartets. When Jones was young, his family moved to Swansea. His father and brother both composed; his mother was accomplished at needlework, which, he said, gave him a love for intricate recurring patterns in a design. He began to compose while he was still a child. Jones took his bachelor's and master's degrees in English Literature at Swansea University in 1934 and 1939, but he had already won recognition as a composer by receiving the Mendelssohn Scholarship in 1935. (He had submitted works he wrote even before his college years). He used the scholarship for study travels to Czechoslovakia, Holland, France, and Germany. His trips to Europe were partly to experience the various cultures there, partly to expand his talent for languages, and partly to experience music. In the meanwhile, he became part of an artistic group based in Swansea that included poets Dylan Thomas and Vernon Watkins and the painters Fred Janes and Kerry Richards. He attended the Royal Academy of Music from 1939, studying viola, horn, conducting (with Henry Wood), and composition. His interest in numbers and complex patterns led him to begin using recurring metric shifts of a pattern of different measure-lengths that would repeat. This allowed him to create melodies of rhythmic ambiguity but with an underlying symmetry and organization. One source of his metrical patterns was nature: he constantly sought to recognize patterns in the environment, and he kept a microscope so he could look for patterns in plants. In World War II, the Army recognized his talents as a linguist and cryptographer, and sent him to the top-secret code-breaking establishment at Bletchley Park, where he specialized in Russian, Rumanian, and Japanese intercepts and documents. Of necessity he did not undertake any composition -- there was not time for that -- but was able to think about musical structures and ideas. He said these years enabled him to assimilate all he had learned about music in his travels and studies. After the war, Jones moved for a year to Cornwall, mostly intending to sketch out ideas and develop his mature style. He destroyed or embargoed the music he had written before the War. His first major compositions emerged from the year in Cornwall: his First Symphony (1945) and First String Quartet (1946). After that he returned to Swansea, where he lived for the rest of his life. Despite not entering the London musical life, he did see his career develop after he won the Royal Philharmonic Prize for an orchestral work, Prologue, in 1950. He came to further attention with his score for a famous radio interpretation of Dylan Thomas' Under Milk Wood, which won the Italia Prize in 1954. After Thomas' death Jones became the trustee of his estate and edited the edition of Thomas' complete poems. He also wrote one of the first notable biographies of the poet, My Friend Dylan Thomas. Jones has said that subconsciously there is always an element of Welshness to his music, though he does not often use folk material. Most of his commissions came from Welsh festivals and organizations.