Admiral of the Fleet Sir John Julian Robertson Oswald GCB (11 August 1933 – 19 July 2011) was a senior Royal Navy officer.

[6] After attending the Royal Navy Staff College in 1964, he was posted to the shore establishment HMS Excellent at Portsmouth as Air Weapons Officer in 1965.

[8] He was posted to the frigate HMS Naiad in September 1966 and promoted to commander on 31 December 1968[9] on his appointment to the Directorate of Naval Plans at the Ministry of Defence.

[7] Oswald became Assistant Chief of the Defence Staff (Policy and Nuclear) in January 1985[7] and went on to become Flag Officer, Third Flotilla and Commander, Anti-Submarine Warfare Striking Fleet in October 1985.

[7] Advanced to Knight Grand Cross of the Order of the Bath in the 1989 New Year Honours,[15] Oswald became First Sea Lord and Chief of the Naval Staff in May 1989.

[17] He was also President of the Sea Cadet Association, vice-president of the Royal United Services Institute and a Trustee of the National Maritime Museum.