Harold Smith was born on 12 May 1880, the son of John and Janet Smith. He joined the Royal Navy as an Acting Engine Room Artificer Fourth Class on 25 March 1902. After service in HMS GOOD HOPE and HMS TERRIBLE he joined submarines on 11 March 1905 and served alternately in the Submarine Depot Ships HMS THAMES and HMS MERCURY until 8 April 1910, although details of submarines served in are not available. He then returned to General Service as a Chief Engine Room Artificer Second Class.

After service in HMS FISGARD, HMS HECLA, and HMS LIVERPOOL, he returned to submarines on 6 October 1912 and joined HMS E2. After operations and patrols in the North Sea, E2 was ordered to the Mediterranean on 16 June 1915 to support the Dardanelles Campaign. E2 completed two patrols in the Sea of Marmara from 13 August 1915 to 3 January 1916. He was specially promoted to Acting Artificer Engineer on 29 February 1916 in recognition of his service in E2. He was confirmed in the rank of Artificer Engineer on 1 December 1917. Harold Smith was awarded the DSC – see London Gazette dated 30 October 1917.

His appointment to HMS L10 as Engineering Officer was dated 1 December 1917. L10 was sunk on the morning of 3 October 1918 by gunfire from the German destroyer S33, after L10 made a torpedo attack on the S33. In making attack on S33 the submarine’s conning tower broached the surface. This was sighted by S33, which then made its gun attack resulting in the loss of L10 with all hands. L10’s attack on S33 was eventually successful as the destroyer was so severely damaged that she had to be sunk by other German forces.

Harold Smith was the husband of Nellie Ruth Smith of Wroxall, Isle of Wight. He is commemorated on the Portsmouth Naval Memorial on Panel No. 28.