For his continued attempts at climbing the slopes of a wadi whilst wounded and under sniper fire, he was awarded the Victoria Cross.
His youngest brother, John, died at the age of 10 in 1913, tripping as he alighted from a moving tram and fracturing his skull.
His middle brother, Percy, also volunteered for the Army, and was killed while serving in the Royal Fusiliers on the Western Front in 1917, aged 19.
He was very interested in military matters and joined The City of London Yeomanry (Rough Riders), a volunteer unit 1908–1911.
At some stage his family moved to Harringay, North London, and he became involved in the Scouting movement shortly after it was established.
After training he was initially posted to the 1st Battalion in France, where he was wounded at the Battle of the Somme in September 1916 at Leuze Wood.
On 1 May 1918 east of the Jordan River, Palestine, in the midst of a pitched battle against Turkish troops, Private Cruickshank volunteered to take a message to company headquarters from his platoon which was in the bottom of a wadi, with its officer and most of the men casualties.
The official War Office citation gave the following account: The platoon to which Private Cruickshank belonged came under very heavy rifle and machine-gun fire at short range and was led down a steep bank into a wadi, most of the men being hit before they reached the bottom.
Private Cruickshank immediately responded and rushed up the slope, but was hit and rolled back into the wadi bottom.
In 1921 he was one of two Lever Brothers ex-servicemen employees who won a ballot to unveil the Port Sunlight War Memorial.
On 29 April 2018, a plaque was unveiled in his honour at Glen Parva Memorial Gardens to commemorate the centenary of his being awarded the VC.
He was Initiated into Freemasonry in St Vedast Lodge, No.4033, (London, England) on 23 September; Passed, 22 October 1925 and Raised on 26 January 1926.