The infantry battalion

The battalion was the basic tactical unit of the infantry of the British Army in the Great War of 1914-1918. At full establishment it consisted of 1,007 men of whom 30 were officers. It comprised a Battalion Headquarters and four Companies.

Battalion HQ

The battalion was usually commanded by an officer with the rank of Lieutenant-Colonel. A Major was Second-in-Command. Battalion HQ also included three other officers: a Captain or Lieutenant filled the role of Adjutant (in charge of battalion administration); a Captain or Lieutenant was the Quartermaster (responsible for stores and transport); and an officer of the Royal Army Medical Corps was attached as Medical Officer.

Battalion HQ also included the Regimental Sergeant-Major (RSM, the most senior Non-Commissioned Officer) plus a number of specialist roles filled by Sergeants: Quartermaster, Drummer, Cook, Pioneer, Shoemaker, Transport, Signaller, Armourer (usually attached from the Army Ordnance Corps) and Orderly Room Clerk.

A Corporal and 4 Privates of the Royal Army Medical Corps were attached to Battalion HQ for water and sanitary duties; a Corporal and 15 Privates were employed as signallers; 10 Privates were employed as pioneers (on construction, repair and general engineering duties); 11 Privates acted as drivers for the horse-drawn transport; 16 acted as stretcher-bearers (these often being the musicians of the battalion band); 6 Privates acted as officers batmen (personal servants) and 2 as orderlies for the Medical Officer.


Judging by the number of men in this photograph, it is an assembled Company of the 3rd (Reserve) Battalion of the Welsh Regiment. [Author's collection]


Usually lettered A to D - or in the case of the Guards and certain other regiments numbered 1 to 4 or lettered W to Z - each of the four companies numbered 227 heads when they were at full establishment. Each was commanded by a Major or Captain, with a Captain as Second-in-Command. Company HQ included a Company Sergeant-Major (CSM), a Company Quartermaster Sergeant (CQMS), 2 Privates acting as batmen and 3 as drivers.

The body of the company was divided into 4 Platoons, each of which was commanded by a subaltern (a Lieutenant or Second Lieutenant). In total, the 4 Platoons consisted of 8 Sergeants, 10 Corporals, 4 Drummers, 4 Batmen and 188 Privates.

Each Platoon was subdivided into 4 Sections, each of 12 men under an NCO.

If asked, after his name, rank and number, a man might refer to himself as being in 3 Section, 1 Platoon, A Company, the Xth Umpshire Regiment.

The day to day "home" for most of the men, and the unit with which they most closely identified, was their Section and Platoon. They would receive orders form their Section Corporal and Lance Corporal, or their Platoon sergeant. They would come into contact with the subaltern in command of their Platoon. The men would also know, if only at a distance in most cases, their company and battalion commanders.

Also on the strength of the battalion

Up to late 1915 each battalion had a Machine Gun Section consisting of a Lieutenant, a Sergeant, a Corporal, 2 drivers, a batman and 12 Privates trained in the maintenance, transport, loading and firing of the Vickers heavy machine gun. These men made up two six-man gun teams.

Also on the strength were 8 Lance-Sergeants and 49 Lance-Corporals (these being included in the figures already given above).

Each battalion had a detachment at its Base Depot, which did not take the field when the battalion was on active service. The Base Detachment consisted - in theory - of a subaltern, 2 Sergeants and 91 Privates to form a first reinforcement (to make good battalion casualties or other losses); 4 Storemen, the Band Sergeant and the Sergeant Master Tailor. When the battalion went on active service, it left behind the Bandmaster and the Sergeant-Instructor of Musketry for service with the Reserve Battalion.

Battalion equipment

Battalion transport consisted of 13 riding and 43 draught and pack horses. The provided the power for drawing the six ammunition carts, two water carts, three General Service Wagons (for tools and machine guns) and the Medical Officer's Maltese Cart. The signallers had 9 bicycles. (Note: the Divisional Train also provided four more two-horsed GS Wagons for each battalion).

Most men carried a rifle - which for the regular battalions (and after the early days when all sorts of older equipment was supplied to the Territorial and Service Battalions, all of these were eventually similarly equipped) was the Short Magazine Lee-Enfield (SMLE). The only exceptions were officers, Pipers, Drummers, Buglers and the five man in each battalion who carried range-finding instruments. All those carrying a rifle, except the RSM and other Staff-Sergeants, were also armed with the sword-bayonet.

Other battalion equipment, over and above that carried by the men, included 120 shovels, 73 pickaxes, 20 felling axes, 8 hand axes, 46 billhooks, 20 reaping hooks, a hand saw, 32 folding saws and 8 crowbars. There was also a plethora of minor stores and spares.

The battalion also carried a certain amount of ammunition, although this was backed up by the echelons of transport at Brigade, Divisional and Lines of Communication levels. When added together, the supply per rifle came to 550 rounds per man. The battalion transport carried 32 boxes of 1,000 rounds, and each man could carry up to 120 rounds. The machine guns were each supplied with a total of 41,500 rounds of which 3,500 was carried with the gun, and 8,000 in regimental reserve.

Changes during the war

By February 1915 the allocation of machine-guns to each battalion had been doubled to 4. This, plus other minor adjustments, changed the full establishment of the battalion to 1,021 men of all ranks. Pioneer battalions, which were introduced in 1915, had 1,034.

In action, battalion machine gun sections were increasingly collected into a brigade group of 16 guns, under a Brigade Machine Gun Officer. This arrangement was made permanent in January 1916: a month later, the gunners were formally transferred from their regiments into the newly-formed Machine Gun Corps. When they lost control of the Vickers guns in this move, the infantry battalions received 4 Lewis light machine guns. By the opening of the 1916 Somme offensive this had been increased to 16 guns per battalion, and early in 1918 this was increased again to 36 guns. The firepower of the battalion was thus considerably increased throughout the war.

Battle experience also led to orders to ensure that battalions would leave behind a number of men when going into action, to form a nucleus for rebuilding, in the event of heavy casualties being suffered. A total of 108 all ranks, consisting of a mix of instructors, trained signallers and other specialists, were to be left out.

The number of men acting as stretcher-bearers was increased from 16 to 32.

Battle reality

Once they had been overseas for a while it was rare indeed for a battalion to be at full establishment. It was not unknown at times for battalions with a nominal strength of over a 1000 men to go into fighting with perhaps only 200.

Equipment was lost and damaged, and not always replaced quickly or fully. Battalion subalterns and CQMS's faced the brunt of continual Brigade and Divisional Staff questions about equipment state and availability. Lucky was the battalion with a wise Quartermaster who knew his way around the Lines of Communication, Brigade and even Engineers dumps and did not shy at "finding" equipment for his battalion.

Certain types of heavy equipment were eventually left in trenches and other positions, being handed over to the relieving unit in exchange for a chit describing the 'trench stores' they had received.

A typical battalion spent perhaps only 5-10 days in a year in intensive action; they would also spend 60-100 days in front-line trench activities without being in action, with the rest of the time being in reserve or at rest, both of which entailed continual effort on fatigues or training.


Battalions of the Scots Guards and the other Highland Regiments were also allowed a Sergeant-Piper and 5 Pipers. Neither the Scottish Lowland or Irish Regiments were allowed this extra strength, although they did have Pipers from within the basic headcount shown above. This was also true of the Tyneside Scottish and Tyneside Irish (Service) Battalions of the Northumberland Fusiliers and even the London Scottish Territorials.

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