To gain experience, in 1919, he entered the Artists' Department in a small publishing house, Graham & Heslip Ltd., and for over five years illustrated countless booklets, and did figure sketches in black and white and colour.
"Oscar" featured a little man with a long nose who wore the baggy trousers of the period known as Oxford bags.
[2] While with the Belfast Telegraph Glenn became a member of the Institute of Journalists, and wrote his own column on topical subjects under the pseudonym "The Gay Philosopher".
[8] He was elected a Member of the Order of Honorary Academicians of the Royal Ulster Academy on 12 January 1968, which entitled him to use the letters R.U.A.
Dublin Opinion was a humorous monthly magazine established in the early days of the Irish Republic and William St. J. Glenn was contributing cartoons from 1928, signed "W. St John.
"[9] Over the next forty years he contributed cartoons often portraying glamorous, sophisticated young men and women, but alongside these, from 1938 he produced a full page scraperboard drawing of country folk in a mythical village called "Ballyscunnion".
[10] In drawing "Ballyscunnion" Glenn used a scraperboard covered in white china that could be inked black and scratched, giving an effect rather like a woodcut.
The "Dorothea" strip attracted favourable attention from the art world for its experimental layout[13] and from women readers for the fashionable style of clothing.
Then after recovering from major surgery for a brain tumour in 1940, he joined the Ministry of Information, working in the photographs and pictures division until 1945.