Owen began illustrating while teaching in his first headship in Croesor, after the school was shut after an outbreak of measles.
The first book he illustrated was Yr Hen Wraig Bach a'i Mochyn (The little old lady and her pig) (1946), which began a demand for his work from Welsh publishers.
[1] As a child, Owen had been an early member of Urdd Gobaith Cymru, a Welsh youth movement, and as an adult he helped by designing and illustrating many of their publications.
Owen was seen as one of the few people who tried to bring a professional quality to illustrations for children in Wales, and took great pride in his work.
He was awarded an honorary MA by the University of Wales in 1997, for his service to Welsh culture and his contributions to Urdd Gobaith Cymru.