Claude Wellesley was born on 29 September 1890, the son of Major E H C Wellesley (J.P. for Wicklow) and Mrs C I Wellesley of Bromley, Kilpedder, County Wicklow, Ireland.

He joined the Royal Navy as a Cadet at the Royal Naval College, Osborne on the Isle of Wight on 15 September 1903 as one of the first intake of seventy four Cadets at that College.  He was promoted to Midshipman on 15 May 1908 and then served in HMS ALBEMARLE, HMS KING EDWARD VII, HMS TALBOT, HMS KENNET, HMS VANGUARD & HMS INVINCIBLE.

Promoted to Sub Lieutenant on 30 May 1911 he then served in HMS HECLA and HMS ACHILLES.  Claude Wellesley was further promoted to Lieutenant on 30 August 1912 before serving in HMS DEVONSHIRE, HMS LOWESTOFT, HMS ARDENT and HMS HECLA.  He was appointed to HMS PRESIDENT ‘additional’ and to HMS VIVID on 14 April 1914 ‘to qualify (E) at Keyham College’.

He was next appointed to HMS DRAKE ‘for Engine Room duties’.  On 24 March 1915 he joined HMS VICTORY ‘for the Oil Fuel Course’ and ‘for the Turbine Course’ before serving in the battleship HMS MARLBOROUGH ‘for E Duties’ followed by HMS BIRKENHEAD ‘for E Duties’.

Claude Wellesley was appointed to HMS DOLPHIN ’additional for E duties’ and ‘for training in Submarines’ on 1 August 1917.  His next appointment was to HMS FEARLESS ‘for Submarine K4 Temporary’ on 23 October 1917 as a temporary replacement for Lieutenant (E) Owen William Phillips who was sick.  He was then appointed to HMS FEARLESS ‘for Submarine K4 for Engineering duties’ on 8 January 1918.

Claude Wellesley died overnight 31 January/1 February 1918 when HMS K4 was sunk after a collision with HMS K6 during the so called ‘Battle of May Island’.  He is commemorated on the Portsmouth Naval Memorial on Panel No.28.