Self-educated Willis depicted many scenes of 19th Century naval warfare and had two oil paintings hung in the Summer exhibition of the Royal Academy at Burlington House in 1941. In 1942 he joined the war effort and served in Destroyers and Combined Operations, landing American tanks on Utah Beach on Normandy D-Day, where he was wounded.
In 1946 he returned to civilian life and continued with his painting with further interest in yachting.