Early service

Peacock served first in the Coldstream Guards, leaving the Army after six years' service. After a few years, he rejoined the Army in 1936, this time in the Green Howards (1st Battalion at Portland). He was stationed in Palestine, where he distinguished himself as a lance-corporal in December 1938 when his unit was attacked on the road between Nablus and Tulkarm. His section was ambushed at close range with rifle fire, but Peacock largely suppressed the attack with well-placed fire from his Bren gun, despite a wound to his head. For his coolness and bravery in action, he was awarded the Military Medal, which was presented by the Princess Royal during a parade at Catterick to mark the Green Howards' 250th anniversary.^[1][2]

World War II

After the German attack on Norway in April 1940, Peacock, now a sergeant, was sent to Norway with his unit.^[1] He distinguished himself in a fighting retreat against the invading forces at Otta in Gudbrandsdalen on 28 April 1940, in circumstances which emphasised his courage, bravery and service readiness. For this action, Peacock was awarded the War Cross with Sword by the Norwegian Minister in London on 20 March 1942.^[3]

After Norway, Peacock's war service took place around the world. In the war's last days Peacock again distinguished himself again in battle at Büchen in Schleswig-Holstein on 1 May 1945, about 45 km east of Hamburg. During this action against effective German resistance, Company Sergeant Major Peacock's company took heavy casualties, including all the officers except an inexperienced 2nd lieutenant and Peacock was left in effective charge. He personally led the attack on Buchen, including an attack on an enemy machine-gun post, and arranged the evacuation of casualties despite heavy and accurate enemy fire. Peacock's assessment and leadership helped to ensure the attack's success and he was rewarded for his part with the Distinguished Conduct Medal.^[1][4][5]

After World War II

After the war he served in Malaya, Cyprus and Hong Kong.

On his return from Malaya, he became Regimental Sergeant Major (RSM) of the Depot at Richmond and during the following three years in this post, he gained a position of great respect. In 1954, he requested a posting as RSM of the 2nd Battalion in Cyprus. The two battalions were subsequently merged and Peacock became 1st Battalion's RSM and went with them to Hong Kong.^[1]

Illness necessitated Peacock's return to England in December 1956, and after a lengthy treatment he became RSM of HQ Northern Command at York on the Long Service List. Peacock's last duty with his Regiment was to take part with the representative party at the funeral of the Norwegian King Haakon in October 1957.^[1]