It was formed on 11 April 1916 under the command of Sir Arthur Paget, with headquarters at Brentwood, Essex.
Its training was disrupted by the need to provide large drafts of reinforcements to the British Expeditionary Force (BEF) on the Western Front.
However, it finally received embarkation orders in February 1917 and left for France.
[4] 71st Division moved into Essex in early March 1917 and concentrated at Colchester where it came under command of Southern Army.
It took over responsibility for the defence of the East Coast from Mersea Island to Walton-on-the-Naze.