[4] From 1 October 1901, the Duke of Connaught held the dual commands of CinC Ireland and GOCinC III Corps.

[4] Pre-war planning for the British Expeditionary Force (BEF) did not envisage any intermediate headquarters between GHQ and the six infantry divisions.

As initially constituted:[9] General Officer Commanding: Major-General William Pulteney Order of Battle at start of the Battle of the Somme, 1 July 1916:[11] General Officer Commanding: Lieutenant-General Sir William Pulteney Order of Battle during the final advance in Artois, 8 October 1918:[12] General Officer Commanding: Lieutenant-General Richard Butler During the Second World War, III Corps was formed in France under the command of Lieutenant-General Sir Ronald Forbes Adam to control forces of the British Expeditionary Force, after the expansion of that force had rendered control by just two corps headquarters cumbersome.

Order of Battle at Dunkirk:[13][14] GOC: Lieutenant-General Sir Ronald Forbes Adam (Lieutenant-General Sydney Rigby Wason after 26 May 1940[15]) After commanding forces in the United Kingdom during late 1940, from the Old Rectory in Whitchurch, Shropshire within Western Command,[24] the corps was used for deception purposes.

It eventually ended up being transferred to Persia and Iraq Command as part of the British Tenth Army, under General Sir Edward P. Quinan.