De Gaspari was born on 30 January 1927, possibly in Varese - or the province of Varese - north of Milan in north-western Italy, not far from the Swiss border. He began his career under the auspices of comic strip artist and illustrator Walter Molino who, in the 1940s, was a leading contributor to Grand Hotel, to which paper De Gaspari also contributed; another strip ('Uragano, il re della prateria' [Hurricane, the King of the Prairie]) appeared in Success Collection published by CEA in 1946-47. De Gaspari also worked for Il Giornalino di Carroccio and illustrated 'il Giustiziere scarlatto' for Albi Mignon.
In May 1947 his first illustrations appeared in La Domenica del Corriere, a Sunday paper which he was to continue contributing to until February 1970, producing over 1,000 illustrations. De Gaspari's paintings were of high quality and innovative in their use of original material, tools and techniques. He would use any sort of paper, create collages and cut and scratch the images. This experimentation with his artwork did occasionally cause him to fall foul of his editors. In one instance, on a Kit Carson cover painting for Cowboy Picture Library, he used real sand glued onto the page; although it made for a superb, textured image, it all had to be scraped off and a new sandy background painted in by an in-house 'bodger' rather than run the risk of damaging the machinery that turned the artwork into four-colour separations.
De Gaspari's first cover in the UK appeared on the Sexton Blake Library in February 1958, gracing Peter Saxon's 'The Sea Tigers'; his second (and last) cover showed his talent for variety, illustrating 'Collapse of Stout Party' by Jack Trevor Story.
De Gaspari thereafter turned his talents to provinding covers for Fleetway's many pocket libraries, including Cowboy Picture Library (30 covers, 1958-60), Thriller Picture Library (39 covers, 1958-60) and Super Detective Library (4 covers, 1960).
However, it was with his work for War Picture Library that he is mainly known in the UK. Beginning with the very first issue in September 1958, De Gaspari produced 32 of the first 48 covers (1958-60); his painting began to appear less frequently after that but were still appearing regularly until 1961, during which period (1960-61) he also contributed 12 covers to Air Ace Picture Library and the debut number of Battle Picture Library (1961). A brief resurgence in 1966 marked the end of De Gaspari's original appearances in the UK, although his work continued to appear, albeit infrequently, on book covers and in Reader's Digest Condensed Books.
Examples of De Gaspari's artwork can be found for sale at the Illustration Art Gallery.