Army organisation in World War II

Since the start of recorded history, in all armies there have been several levels of command so that forces can be effectively ordered and controlled. The nature of World War II as a global conflict meant that combat operations either took place or were readied in several disparate geographical theatres, and the size and dispersed nature of the forces involved added to the number of command levels. At the very top, therefore, national leaders decided the aims of their nation’s war and at the grand strategic level directed the progress of their forces’ operations via the agency of their uniformed chiefs-of-staff. Theatres of war had commanders-in-chief, who controlled the land, naval, and air forces operating in that theatre. Thus the American General Dwight D. Eisenhower, as Supreme Allied Commander Europe, received his directives for the ‘Overlord’ landing in Normandy on 6 June 1944 from the Anglo-US Combined Chiefs-of-Staff and operated, together with his deputy, the British Air Chief Marshal Sir Arthur Tedder, through his three British single-service commanders, namely Admiral Sir Bertram Ramsay for the Allied naval forces, General Sir Bernard Montgomery for the land forces, and Air Chief Marshal Sir Trafford Leigh-Mallory for the air forces.

It should be noted here that, in a military context, a command is a collection of formations and units under the control of a single officer. As such a command is generally an administrative and executive strategic headquarters which is responsible to the national government or the national military headquarters. A formation is a composite military organisation which includes a mixture of integrated and operationally attached sub-units, and designed to be capable of sustained and self-contained combat operations, i.e. without outside support. Armies, corps, divisions and, to a limited extent, brigades can therefore be regarded as formations. Farther down the scale, is the unit, which lacks this self-sustained capability for combat operations, and is thus a homogeneous military organisation (combat, combat support or non-combat in capability) that includes service personnel predominantly from a single arm or branch of service and with organic administrative and command functions. Brigades, regiments and battalions can therefore be regarded as units, and anything below this level (company, platoon and section/squad) is a sub-unit or minor unit.

Formations and units
The normal command levels for formations are:

  • army groups of typically 400,000 men commanded by a field marshal or general and conventionally represented on maps by a rectangle (surmounted by xxxxx),
  • armies of some 150,000 men commanded by a general or lieutenant general (xxxx),
  • corps of some 40,000 men commanded by a lieutenant general or major general (xxx),
  • divisions of some 12,000-14,900 men commanded by a major general (xx), and
  • brigades of some 2,500 men commanded by a brigadier general (x).

Below this are the units and sub-units, which are:

  • regiments of some 2,000 men commanded by a colonel (three vertical lines)
  • battalions of some 750 men commanded by a lieutenant colonel (two lines),
  • companies of some 125 men commanded by a major or captain (one line)
  • platoons of some 35-40 men commanded by a lieutenant (three dots), and
  • sections or squads of some 10 men commanded by a NCO (one dot).

An army group comprised between two and five armies, but did not feature in the organisation of all armies. The Soviet term for an army group was a front, and during the early part of what the USSR termed the Great Patriotic War, starting with the German invasion of June 1941, the Soviets also had another command level, the theatre (or direction) as the command level between the Stavka (general staff) and fronts. There were three directions, but the concept of the direction had been discontinued by the summer of 1942. The Japanese also employ no army groups as such, but defined this level of command as the general army (most of them with a geographic title), which commanded two or more area armies basically equivalent to a western army. Thus, the Southern Area Army controlled the 25th Army that overran Malaya and Singapore, the 15th Army that invaded Burma, and the 14th Army that conquered the Philippine islands.

Specialised armies
All nations employed armies, and it was at this level that specialised roles began to be reflected in their titles. In the North-West European campaigns of 1944/45 both the Germans and the Western Allies had airborne armies: the German 3rd Parachute Army fought only in the ground role, but the Allied 1st Airborne Army supervised the airborne operations during the ‘Overlord’ landings, Operation ‘Market’ designed to seize the Rhine crossings at Arnhem, and Operation ‘Varsity’ that seized an airhead on the eastern bank of the Rhine.

The Germans also had the 20th Mountain Army, which operated in northern Finland and Norway, and also a number of Panzer armies, which started to emerge from Panzer groups toward the end of 1941 as formations comprising tank and mechanised/motorised infantry forces. In 1945 the Germans also had two Waffen-SS armies, the 6th and 11th SS Armies.

The Soviets also had tank armies as well as shock and guards armies. Shock armies were strengthened formations employed in breakthrough operations, while tank armies were used to exploit such breakthroughs. The guards designation was an honorific awarded to armies which had distinguished themselves in combat and were then employed as elite troops in especially difficult situations.

The Japanese had only conventional formations. Area armies were responsible for a particular operational area and had overall command of all formations deployed in it. For example, the Burma Area Army both oversaw the operations conducted by several Japanese armies against the British and was responsible for the internal security of the country. A Japanese army performed the same function as a British or US corps as it commanded a number of divisions. It should be noted, however, that the Chinese armies which fought in the Burma campaign were of a size equivalent to a British or US division.

Corps and divisional organisations
Except for those of the Japanese, the armies of all combatant nations comprised between two and five corps and army troops (additional artillery, engineers, and logistics units). A corps was in essence a small army, but corps varied very greatly in size. A Soviet tank corps, for example, had about 11,000 men, 210 tanks and 200 pieces of artillery, and was therefore comparable to a British or US armoured division: this is reflected in the fact that the Soviet tank corps had no subordinate divisions, and in its 1944 form was therefore built round three tank brigades, one mechanised infantry brigade, three self-propelled artillery regiments, and single mortar, anti-aircraft, rocket-launcher and motorcycle regiments.

The standard corps could comprise as many as five divisions. The most common type of division was the infantry (in the Soviet army rifle) division. The composition of an infantry division varied in establishment as the war progressed, and in combat were often somewhat below establishment strength. The US infantry division, for example, in July 1943 had some 14,250 men as 9,350 in three 3,120-man infantry regiments each with supporting elements, 2,160 men in one medium artillery battalion (12 155-mm howitzers) and three light artillery battalions (54 105-mm howitzers) as well as 57 57-mm anti-tank guns, supporting elements, together with auxiliary and medical elements. The division’s weapons also included some 6,520 rifles, 254 automatic rifles, 157 0.3-in machine guns, 236 0.5-in machine guns, 90 2-in mortars and 54 3-in mortars. In action the division often had additional elements, such as tanks, tank destroyers and anti-aircraft guns, attached to it.

In the Japanese infantry division, commanded by a lieutenant general, the infantry elements were controlled by an infantry group headquarters commanded by a major general, who might have other elements assigned to him for specific missions.

British and commonwealth divisions comprised two or three brigades, each about equivalent to a German, Japanese and US infantry regiment in capability.

However, the US armoured division during the second half of the war comprised three tank and three infantry battalions, which were organised operationally into three combat commands.

Brigades and lower
Brigades and regiments within divisions usually consisted of three battalions of the same type, with infantry regiments often also each having an anti-tank gun company and a light howitzer company, although British and commonwealth armoured brigades had three tank battalions and one motorised infantry. Armies which did not have divisional brigades employed brigades elsewhere. The Soviets had tank and mechanised brigades in their tank and mechanised corps, and early in the war also deployed independent tank brigades. Other nations also had independent brigades which had their own artillery, engineers, and logistical units. The Japanese termed these as independent mixed brigades, to which the British equivalent was the brigade group.

The brigade was the lowest formation, while though below it (battalions, companies, platoons, and squads/sections) were units and sub-units. This meant that while battalions might be moved between brigades, parts of battalions never were, except on occasion very temporarily for particular operations. A measure of confusion is added by the fact that the British gave the designation regiment to their reconnaissance, tank (as did the Japanese) artillery, and engineer battalions.

War-time changes were concerned largely with the strengthening of heavy weapons elements. Tank battalions varied in strength from nation to nation and during various phases of the war: they comprised companies and platoons, and in British service, squadrons and troops. Field artillery battalions generally comprised three batteries each of six to eight guns, while medium and heavy artillery battalions had 12 to 16 guns.