Born in Wales, the son of a wealthy iron founder, Morris was educated at Charterhouse and the Royal College of Music. He studied in Paris, Rome and Berlin. Later (1947) he became a Baronet.

Morris met Alfred James MUNNINGS who encouraged him to come to Cornwall in 1916. Living at Zennor for a year he began to teach himself to work in watercolour, making studies of plant and insect life. Meeting Arthur LETT-HAINES soon after WWI, they formed a friendship that was to last both for the remainder of their lives.

They moved to Newlyn in 1919 and visited thereafter frequently during the 1920s while primarily living in London. Morris mainly worked in the realist tradition of portraiture, and scenes of buildings and harbour scenes. Amongst their artistic friends he became known as the 'Cezanne of Newlyn' and he was influential; Ernest PROCTER was especially interested in his techniques with oils, which were self taught.

By 1927 Lett and Cedric had moved to London full-time, and in 1936, they moved together to Suffolk and founded the East Anglian School of Painting and Drawing, which was to become an important centre of modernist art.