The British Corps of 1914-1918

The British Corps
The Corps was an intermediate level in the command chain. It reported up to an Army, and commanded Divisions. The Corps HQ also had a number of units durectly under its command.

Note: the army used the word Corps in a number of different ways, too. One infantry regiment was called the King's Royal Rifle Corps. The artillery, engineers, transport, ordnance and various other arms of the service were also known as Corps. These are quite different meanings from the organisational entity described on this page.

I Corps

Organised during pre-war planning of BEF. Proceeded to France August 1914 as part of original BEF, under the command of Sir Douglas Haig. First engaged in the Battle of Mons but peripherally. Then

II Corps

Organised during pre-war planning of BEF. Proceeded to France August 1914 as part of original BEF, under the command of Sir James Grierson, soon succeeded by Sir Horace Smith-Dorrien. First engaged in the Battle of Mons.

III Corps

Formed in England on outbreak of war and took command of Divisions in France on 31 August 1914 under Sir William Pulteney. First engaged in the Battle of the Marne.

IV Corps

Moved to Belgium in October 1914, under the command of Sir Henry Rawlinson, under orders to assist the defence of Antwerp. Along with I Corps, took brunt of heroic defence at First Battle of Ypres.

V Corps

Moved to France January 1915. First engaged in battle of Neuve Chapelle.

VI Corps

Formed in France on 1 June 1915 and placed under Lt-Gen Sir J. L. Keir. First seriously engaged in the Ypres area in the second attack on Bellewaarde, a diversionary action to the attack at Loos.

VII Corps

Formed in France on 14 July 1915 and placed under Lt-Gen Sir T. d'O. Snow. First seriously engaged in the Somme offensive.

VIII Corps

Formed at Gallipoli as the British Army Corps in May 1915 and renamed VIII Corps in June 1915. Commanded by Lt-Gen Sir Aylmer Hunter-Weston. Moved to France in March 1916. Had major responsibility for failure of northern sector of British offensive on the Somme, 1 July 1916, and was never again responsible for a major offensive. Disbanded in June 1918.

IX Corps

Formed for Suvla Bay operations at Gallipoli which commenced August 1915. Commanded by Lt-Gen Sir Frederick Stopford. Moved to France a year later, with its first serious engagement at Messines in June 1917.

X Corps

Formed in France on 14 July 1915 under Lt-Gen Sir T. N. Morland. First serious engagement on Somme in July 1916. Remained in the Ypres area and Flanders throughout the war.

XI Corps

Formed in France on 29 August 1915 under Lt-Gen R. Haking. First serious engagement a disaster at Fromelles, a diversion to the Somme offensive. Moved to Italy in November 1917 but returned to France March 1918.

XII Corps

Formed in France on 6 September 1915 under Lt-Gen Sir H. F. M. Wilson. Moved next month to Salonika.

XIII Corps

Formed in France on 15November 1915 under Lt-Gen Walter N. Congreve. First seriously engaged on the Somme in 1916.

XIV Corps

Formed in France in 3 January 1916 under Lt-Gen the Earl of Cavan. First seriously engaged on the Somme in 1916. Moved to Italy in November 1917 and temporarily became GHQ for that theatre in April 1918. reformed as XIV Corps in October 1918.

XV Corps

Formed in Egypt on 9 December 1915 but effectively disbanded and reformed in France on 22 April 1916 under Lt-Gen Sir Henry Horne. First seriously engaged on the Somme in 1916.

XVI Corps

Formed in Salonika under Lt-Gen George Milne.

XVII Corps

Formed in France on 9 January 1916 under Lt-Gen Sir Julian Byng. First seriously engaged at Arras in 1917.

XVIII Corps

Formed in France in January 1917 under Lt-Gen Sir Ivor Maxse. First seriously engaged in the pursuit of the enemy withdrawal to the Hindenburg Line. Merged into VIII Corps in July 1918.

XIX Corps

Formed in France in February 1917. First seriously engaged in the Third Battle of Ypres.

XX Corps

Formed in Egypt in June 1917 under Lt-Gen Sir Philip Chetwode.

XXI Corps

Formed in Egypt in June 1917 under Lt-Gen Sir Edward Bulfin.

XXII Corps

Formed in France in December 1917 from what had been II ANZAC. First seriously engaged at the Battles of the Lys in which it incurred heavy losses and was not fit to return to action for several months.

Reserve Corps

Formed in France in April 1916 under Lt-Gen Sir Hubert Gough, it became the Reserve Army (which later became Fifth Army) in May 1916 and was first engaged in the Somme offensive.

Indian Corps

Formed in France in September 1914, in command of the Meerut and Lahore Divisions, under Lt-Gen. Sir James Willcocks. Disbanded December 1915.

Australian and New Zealand Army Corps (ANZAC)

Formed for operations at Gallipoli, it was later (February 1916) renamed I ANZAC and then (December 1917) Australian Corps. Moved to France in 1916. Eventually grew to command of all five Australian Divisions. From formation, the Australian Divisions always remained together as a national Corps. They were not affected by the reduction of brigades from four to three battalions, as happened to British formations in early 1918.

Canadian Corps

Formed when the 2nd Canadian Division moved to France in September 1915, and placed under Lt-Gen Sir E. Alderson. Later command by the Hon Sur Julian Byng (May 1916) and later Sir Arthur Currie (from June 1917 onward). Eventually grew to command of all four Canadian Divisions. From formation, the Canadian Divisions always remained together as a national Corps. They were not affected by the reduction of brigades from four to three battalions, as happened to British formations in early 1918.

Cavalry Corps

Formed in France in October 1914 under Sir Edmund Allenby. Broken up in March 1916 but re-established in September of that year.

Indian Cavalry Corps

Formed in France in December 1914 but broken up in March 1916.

Tigris Corps

Formed in Mesopotamia in April 1916 when .

I Indian Corps

Formed in Mesopotamia in November 1916.

II Indian Corps

Formed in Mesopotamia in April 1915.

III Indian Corps

Formed in Mesopotamia in December 1915. Was also called the Tigris Corps. Split into two in November 1916, one part becoming Tigris Corps, the other I Indian Corps.

Desert Mounted Corps

Formed in Egypt in August 1917.

XXIII Corps

Formed in England in February 1918 and remained there.

XXIV Corps

Formed in Egypt in March 1918 but disbanded after just a week.

What comprised a Corps?

Early days

A Corps was a formation of the army that in 1914 was composed of two Divisions, plus a Signals Cable Section of the Royal Engineers to provide communications. It was properly titled an 'Army Corps', but the full name was usually shortened. Corps, normally commanded by a Lieutenant-General, reported up to GHQ, and later, to Army HQ. (Although in the smaller theatres where there was no Army level, Corps usually reported to HQ or GHQ). The Corps HQ consisted of 18 officers and 71 other ranks. The Divisions were permanently attached to their Corps.

Development during the war

As the army grew in size the composition of the Corps changed considerably. The number of Divisions under the command of the Corps remained nominally at two, but could be increased if fighting conditions required. Divisions were now moved from Corps to Corps as they came in and out of the line and were moved from place to place. The Corps HQ generally remained fixed in place, while the Divisions were moved around. Corps were gradually given more responsibility for the supply lines and other features of their area, so the specialist units directly under Corps command also increased. The latter included heavy artillery, from April 1916 onwards.

By the late stages of the war, Corps HQ had grown to consist of 50 officers and 141 other ranks. Corps troops included a cavalry regiment, the heavy artillery (including a motor transport company), a heavy trench mortar battery, a cyclist battalion, signal troops, a motor transport column, mobile workshops of the Army Ordnance Corps an an Area Employment Company. In all, this would amount to perhaps 2000 officers and men, depending on the Divisions under command at any time. The establishment varied in theatres other than the Western Front, and were generally smaller.