He was removed from command in mid-1916, however, as a result of political manoeuvring following the attempt to find a scapegoat for the failed Actions of St Eloi Craters in March 1916.
[5] He then gained a Regular Army commission in the 19th Hussars on 28 June 1882, in time to see action with the regiment at Kassassin (28 August) and Tel-el-Kebir (13 September) in the Anglo-Egyptian War.
[12] He returned to his regiment in 1893, with a promotion to major,[13] and stayed with them until 1897, when he was appointed to a two-year term as an assistant military secretary in India.
[7] Fanshawe served throughout the Second Boer War, where he received a brevet promotion to lieutenant colonel and was mentioned in dispatches twice (including by Major General Lord Kitchener dated 23 June 1902).
[19] He was transferred to India later in the year, to command the Presidency Brigade in the Indian Lucknow Division, and was promoted to temporary brigadier general in December.
[12] At V Corps, Fanshawe oversaw the initial actions of St Eloi Craters in late March 1916; the attack under his command by the 3rd Division was successful, but terrible ground conditions made it hard for them or for the relieving troops in the Canadian Corps, to hold ground, and after a month of heavy losses, the line stabilised at the original positions.
Instead, Major-General Aylmer Haldane, GOC 3rd Division, was lined up as a scapegoat; Fanshawe tried to intervene with General Sir Douglas Haig, the commander-in-chief (C-in-C) of the British Expeditionary Force (BEF) on the Western Front, and was sacked on 4 July.
He commanded it through the end of the war, including at the Battle of Sharqat, the final engagement of the campaign in the Middle East.