Henry was the son of Dr. J O’Donnell of Cashel, Co. Tipperary. He attended the Catholic University School in Dublin and after this his art education started and lasted about eight years. He began in the Dublin Metropolitan School of Art under Sean Keating P.R.HA., he then moved to London where he studied at St. John’s wood School and then at Westminster Art School under Walter Bayes R.B.A.,R.W.S. For the next fifty two years he exhibited his work at the various exhibitions such as The Municipal Art Gallery and Museum Belfast & Plymouth, The Grafton Gallery London, The Egan Salon Dublin, Royal Academy London, Royal Hibernian Academy London and according to O’Donnell’s note The Hacker Gallery in New York these are to name but a few.