He held a number of other senior posts in the British Army, having begun his military career in the ranks during the Second World War.
[3] Now a war substantive lieutenant, he briefly transferred to the Royal Fusiliers from 14 June 1941,[4] and then to the Reconnaissance Corps on 15 July,[5] and finally to the Parachute Regiment on 19 October 1943.
[10][11] For two years prior to this he had served as a General Staff Officer Grade II in the Infantry Directorate at the War Office, working on standardisation of infantry weapons with his Belgian, Canadian and American counterparts, this work led to his appointment as a Member of the Order of the British Empire (MBE) in the 1953 Coronation Honours.
[2][31] His obituary in The Times states that he "was regarded by many as the best and most successful Director of Operations in Northern Ireland in the 1970s and 1980s",[2] though it also notes that he himself would be happy to attribute much of the preparatory work to Tuzo (who has been described in similar terms).
[32] His success was attributable to a number of factors: he regularly visited the troops on the ground which gave him a good picture of the difficulties faced in particular areas; once a unit or commander had proved itself, he was happy to delegate considerable authority, in particular to his immediate subordinate, Commander Land Forces (Sir) Peter Leng; he had a good relationship with the Secretary of State for Northern Ireland, Merlyn Rees, who said of King "You have never played at politics and I have never played at being a soldier; that's why we have got on so well.
[36] He delivered the Kermit Roosevelt lectures in the United States' staff colleges in 1977,[2] and relinquished his appointment on 30 September 1978,[37] and retired from the army on 27 December 1978.