While at Barnsley Grammar School in the 1960s his music teacher played a recording of Berg's Violin Concerto, which had a lasting influence.
[2] He attended the Warsaw Academy of Music between 1971 and 1972, where he studied with Andrzej Dobrowolski but also met and became friends with Witold Lutosławski.
Works such as the orchestral Orion Over Farne (1984), the unaccompanied choral work To Fields We Do Not Know (1985), (described as "a Northumbrian elegy"), the orchestral song-cycle Still Mine (1992), the ensemble piece Winter Reels (2010) and the choral Uncertain Sea (2014) have all drawn inspiration from Northumberland.
[4] Casken has also composed two operas: Golem (1988), which has been revived frequently,[1] and God's Liar (2000), the latter based on Tolstoy's novella Father Sergius.
[1] Recent work has shown a renewal of interest in musical theatre, with the melodrama Deadly Pleasures for narrator and small ensemble, based a poem by D M Thomas concerning the life of Cleopatra, and a monodrama, Kokoschka’s Doll, premiered at the Cheltenham Festival in 2017, about Alma Mahler's relationship with the painter Oskar Kokoschka.