Walter Simpson was born in Blackburn in Lancashire on 19 March 1920, the son of Walter and May Simpson of Blackburn, Lancashire.

He joined the Royal Navy on a twelve year Continuous Service Engagement. A volunteer for ‘Special Service’ he trained as a charioteer No 2 Crewman at HMS VARBEL. He was the No. 2 Crewman on Chariot No. XXIII launched from HMS THUNDERBOLT on 3 January 1943 for an attack on Italian Shipping at Palermo. His No.1 Crewman was Petty Officer Miln. At the time of the launch the conditions were not ideal. On their run into the harbour their chariot experienced a battery explosion. As a result of the explosion the chariot’s buoyancy chamber flooded and it went into a rapid dive. Walter Simpson was unable to get clear of the chariot despite efforts by Petty Officer Miln to free him. Miln managed to get himself to the surface from some ninety feet depth, got himself ashore and ended up as a Prisoner of War. Walter Simpson was assumed to have drowned.

His body was recovered and he was buried in the Catania War Cemetery in Sicily in Grave No. II. F. 18.  He is commemorated on the 12^th Submarine Flotilla memorials at Rothesay on the Isle of Bute and at Kylesku.