Harold Chapman was born in Adelaide, Eastern Cape, South Africa on 5 August 1910, the son of Harold and Winifred Lucretia Chapman. On 12 September 1927 he arrived in Southampton in the Union Castle Steamship Company’s SS ARUNDEL CASTLE as a ‘Colonial’ Naval Cadet joining the Royal Navy at HMS EREBUS. He was promoted to Midshipman on 1 January 1929 and, on 21 January 1929 he was appointed to the cruiser HMS LONDON in the Mediterranean Fleet. In July 1931 Acting Sub Lieutenant Harold Chapman (Seniority 1st May 1931) was serving at the Royal Naval College, Greenwich ‘for Lieutenants Courses’ to which he had been appointed on 30 April 1931 and, on 4 April 1932 he was appointed to Portsmouth ‘for his ‘G’, ‘T’ and ‘N’ Courses’.

Harold Chapman was appointed to HMS DOLPHIN ‘for Submarine Training’ on 8 May 1933 and, on 19 August 1933 he was appointed to HMS DOLPHIN ‘for Submarine L54 as Third Hand’. He was promoted Lieutenant on 1 July 1934. In January 1935 he was serving in the Submarine Depot Ship HMS MEDWAY at Hong Kong ‘for Submarine HMS PARTHIAN as 4th Hand’ to which he had been appointed on 16 December 1934. On 20 December 1936 he was appointed to the Submarine Depot Ship HMS TITANIA  at Portsmouth. This was followed by an appointment to the Submarine Depot Ship HMS LUCIA  at Devonport ‘for Submarine HMS SEAHORSE as First Lieutenant’. He was appointed to ‘Submarine HMS THETIS as First Lieutenant – standing by whilst completing’ at the Cammell Laird Shipyard at Birkenhead on 23 May 1938.

Harold Chapman, who died in the accidental loss of HMS THETIS in Liverpool Bay on 3 June 1939 was the husband of Inez Ruth Chapman of White House, Frensham, Surrey and they had a daughter, Felicity Anne, aged two at the time of the accident. Following the accident and the recovery of the submarine, Harold Chapman was buried in the THETIS Mass Grave at Holyhead.