Geoffrey Harper was born in Patea, New Zealand, 21 November 1894. He was educated at Huntley School and Wanganui Collegiate School, New Zealand.

He joined the Royal Navy and served on HMS Highflyer, 1913-14, HMS Endymion, 1914, HMS Dreadnought, 1914-16, HMS Godetia, HMS Daphne and HMS Devonshire, 1916, and HMS Courageous. 1916-17. He was promoted Acting Lieutenant, 1917, and Lieutenant, 1918, and served on HMS Indomitable, 1918-19. He joined HMS Odin and saw action in Somaliland (Somalia), 1919-20. He retired from the Navy, 1931.

He was employed as a teacher at St Michael's School, Uckfield, 1931-5, and Assistant Superintendant at the Lancashire and Cheshire National Sea Training Home for Boys, Wallasey, 1935-6. He became private secretary to the Governor of the Leeward Islands, 1936-8.

He rejoined the Royal Navy and was assigned to HMS Lucia off the coast of East Africa, 1939-40. He was Fleet Navigating Officer, Ceylon (Sri Lanka), 1940-2; Assistant King's Harbour Master, Sheerness, 1942-4; and Captain Superintendant, Tricomalee, 1945-7. He retired in 1948.

He remained in Ceylon, working as a teacher in Colombo, 1949-54, and bursar at St Thomas' College, Guritalawa, 1954-6. He settled in Umtali, Southern Rhodesia (Zimbabwe), 1956-8; Durban, South Africa, 1958-61; and Malta, 1961-2. He died on 1 October 1962.