His first language was Welsh, and he was heavily committed to Wales and its music. Alun Hoddinott, William Mathias and Grace Williams all wrote music for his distinctive voice. But he had a very broad repertoire, encompassing, for example, Bach Passions, Gilbert and Sullivan, Janáček and Elgar's The Dream of Gerontius.
He sang at the Investiture of the Prince of Wales in 1969 and at the opening of St David's Hall, Cardiff in 1982. He founded the London Welsh Chorale in 1983 and was the group's conductor until 2008.
From the late 1960s he taught at the Royal Academy of Music in London, where he became head of vocal studies in the mid-1980s.
Kenneth Bowen died in Cheltenham on 1 September 2018, aged eighty-six. His two sons, in a very real sense, continue his work - Geraint Bowen is Director of Music at Hereford Cathedral, and Meurig Bowen is Head of Artistic Planning at the BBC National Orchestra of Wales.