Gilbert Oxley was born on 21 January 1882 at Elsecar, Yorkshire, the elder of two sons of George Oxley, a boilermaker, and his wife Alathea (née Hoyland).

After serving an apprenticeship as a boilermaker, he joined the Royal Navy in June 1904 at HMS FIREQUEEN II, a tender to HMS FISGARD, the Artificer training ship at Portsmouth. After training, he joined the cruiser HMS HERMES deployed to the Cape of Good Hope station, and was rated ERA 3rd class in June 1907. In January 1909 he joined the depot ship HMS MERCURY, at that time commanded by the Inspecting Captain of Submarines. In October 1910 he returned to the surface Navy, serving a series of short drafts in HMS DUNCAN, CORNWALLIS, HAMPSHIRE, TRIUMPH and GOOD HOPE, and training ship roles in EXMOUTH and FISGARD.  He was rated ERA 2nd Class in June 1911.

He joined HMS DOLPHIN in May 1914, and in September that year was drafted to HMS ADAMANT for HMS D6. D6 was at that time part of the large Eighth Submarine Flotilla based at Harwich, but in August 1915 D6 transferred briefly to the Fourth Flotilla (at Dover), moving back in October 1915 and then transferring to the Tenth Flotilla (possibly at the Humber) in August 1916. Gilbert Oxley’s service history records his administrative transfer between the depot ships ADAMANT, MAIDSTONE, ARROGANT and VULCAN reflecting the employment of D6. He was advanced to ERA 1st Class in June 1916.

ERA Oxley was lost overboard from HMS D6 and drowned on 11 September 1916.  His body was not recovered. According to CWGC he left a widow, Grace Annie Oxley, of Beeston Hill, Leeds, but no further details of her have been found.

Gilbert Oxley was awarded a Mention in Despatches for his service in submarines, but this was only gazetted after his death.

He is commemorated on the Portsmouth Naval Memorial