British Army Hierarchies
See also Constitution of the Military Forces of the British Crown, which gives the contemporary legal definition of the British Army and lists the main administrative units.
Units, formations and regiments
The British Army had two hierarchies:
- Administrative
- Tactical
These were separate at higher levels but overlapped at lower levels. There was also a separate hierarchy of pay offices that we haven't yet tried to represent on this site.
- Regiments/corps were administrative. Their member units served in many different formations at the same time. We class these as either infantry regiment (administrative) or corps (administrative).
- Formations were tactical. Their member units could be from different regiments, of different types, and even of different nationalities. There were several different types of formation, such as infantry brigade, infantry division and corps (tactical),
- Units, such as infantry battalions, were tactical and administrative at the same time.
Administrative hierarchy
- Arm (infantry, cavalry or artillery; this level doesn't have its own page for other types of unit)
- Record office
- Regiment/corps (either infantry regiment (administrative) or corps (administrative))
- Identity (an intermediate level between regiment and unit that only applies in some cases)
- Units (see below)
Formation hierarchy
This is a typical hierarchy based on the Western Front, but there were all sorts of non-standard formations in other theatres, especially in Africa and Asia.
- General Headquarters (usually one per theatre; sometimes synonymous with Expeditionary Force, sometimes not)
- Lines of Communication (under GHQ in each theatre)
- Army (not used in every theatre)
- Corps (not used in every theatre)
- Division (can be infantry division or mounted division)
- Brigade (can be infantry brigade, mounted brigade or tank brigade, but artillery brigades are classed as units)
Units could be direct members of any level of formation. Above brigade level this was in groups known as Divisional Troops, Corps Troops, Army Troops, or GHQ Troops .
Units and sub-units
There are many different types of units. This section shows the main ones for infantry, cavalry and field artillery. Each unit was divided into smaller units, sometimes known as sub-units. These sub-units are generally not represented by separate pages on this site unless they sometimes operated independently of their parent units, but they are shown here for information.
| Infantry | Cavalry | Field artillery | |
|---|---|---|---|
| Unit | Infantry battalion | Cavalry regiment | Field artillery brigade |
| Sub-unit | Infantry company | Cavalry squadron | Field artillery battery |
| Sub-unit | Infantry platoon | Cavalry troop | Field artillery section |
Infantry platoons were further divided into sections of about 12 men.
A Royal Engineers company was a similar size to an infantry company but for many types of engineers was the largest unit, attached directly to a formation.
Cavalry squadrons could be attached directly to an infantry division, separately from their parent regiments.
Regulars and Territorials
Each unit of the British Army belonged to one of these branches:
- Regular Army
- Territorial Force (including the Yeomanry, which was the Territorial cavalry)
- Special Reserve
- New Army
These classifications apply at unit level and don't follow the administrative hierarchy: most infantry regiments contained battalions of all types.
Except for Special Reserve, they can also apply to formations at Brigade and Division level, but are usually meaningless at higher levels.
There was also the Volunteer Training Corps, which was originally a separate unofficial service but became a branch of the British Army later in the war.
Examples
Infantry battalion
Example hierarchies for 1/5th Battalion Lincolnshire Regiment, which was a battalion of the Territorial Force.
Infantry administrative hierarchy
- Arm: British Infantry Arm
- Record office: Lichfield Infantry Record Office
- Regiment/corps: Lincolnshire Regiment
- Unit: 1/5th Battalion Lincolnshire Regiment
Infantry tactical hierarchy
Same battalion's tactical hierarchy, 1 July 1916 (sources: gommecourt.co.uk; WO 95/2691):
- Formation: British Expeditionary Force (ie Western Front)
- Formation: Third Army
- Formation: VII Corps
- Formation: 46th Division
- Formation: 138th Infantry Brigade
- Unit: 1/5th Battalion, Lincolnshire Regiment
Regular Cavalry
Example hierarchies for 7th Dragoon Guards.
Cavalry administrative hierarchy
- Arm: British Cavalry Arm
- Record office: Canterbury Cavalry Record Office
- Regiment/corps: Corps of Dragoons
- Unit: 7th Dragoon Guards
Cavalry tactical hierarchy
Same regiment's tactical hierarchy, 14 July 1916 (source: David Kenyon's PhD thesis, pp. 50-56):
- Formation: British Expeditionary Force (ie Western Front)
- Formation: Fourth Army
- Formation: XIII Corps
- Formation: 2nd Indian Cavalry Division
- Formation: 9th Indian Cavalry Brigade (also known as Secunderabad Cavalry Brigade)
- Unit: 7th Dragoon Guards
The cavalry divisions on the Western Front were sometimes part of a tactical formation called Cavalry Corps, which should not be confused with the administrative corps of Dragoons, Hussars and Lancers.
