Cuneo began his artistic career as an illustrator, but it was his work as war artist which brought him national recognition. During the Second World War whilst serving briefly with the Royal Engineers, Cuneo was the artist for the Illustrated London News in France. From 1941 he served as an official war artist, producing propaganda paintings for the Ministry of Information, and also illustrated the book ‘How to Draw Tanks'. In post war Britain, Cuneo became the establishment artist for much of the latter half of the twentieth century. As official artist at Queen Elizabeth II's coronation in 1953, his name was put before the public worldwide. Although a painter of portraits, he was also an artist of landscapes and industry renowned for his works portraying mines, dams, industrial processes, but above all his railway scenes. His largest painting (20 ft × 10 ft), commissioned by the Science Museum in 1967, was of the concourse at Waterloo Station. He was also famous for putting a mouse in his paintings; this first appeared in 1953 and subsequently in most of his paintings thereafter. He was appointed OBE in 1987 and CVO in 1994. A statue to his memory at Waterloo Station was unveiled in October 2004.