Infantry Battalion

A battalion is a military unit, typically consisting of 300 to 1,200 soldiers commanded by a lieutenant colonel, and subdivided into a number of companies (usually each commanded by a major or a captain). In some countries, battalions are exclusively infantry, while in others battalions are unit-level organizations.

The word battalion came into the English language in the 16th century from the French language ( French: ''bataillon'' meaning "battle squadron"; Italian: ''battaglione'' meaning the same thing; derived from the Vulgar Latin word ''battalia'' meaning "battle" and from the Latin word ''bauttere'' meaning "to beat" or "to strike"). The first use of the word in English was in the 1580s.

Description

A battalion comprises two or more primary mission companies which are often of a common type (e.g., infantry, tank, or maintenance), although there are exceptions such as combined arms battalions in the U.S. Army. In addition to the primary mission companies, a battalion typically includes a headquarters staff and combat service support which may be combined into a Headquarters and service company. A battalion may also contain a combat support company. With all these components, a battalion is the smallest military unit capable of "limited independent operations".

The battalion must have a source of re-supply to enable it to sustain operations for more than a few days. This is because a battalion's complement of ammunition, expendable weapons (e.g., hand grenades and disposable rocket launchers), water, rations, fuel, lubricants, replacement parts, batteries, and medical supplies normally consists of only what the battalion's soldiers and the battalion's vehicles can carry.

The commander's staff coordinates and plans operations. A battalion's subordinate companies and their platoons are dependent upon the battalion headquarters for command, control, communications, and intelligence, and the battalion's service and support structure. The battalion is usually part of a regiment, group, or brigade depending on the branch of service.

NATO

NATO defines a battalion as "larger than a company, but smaller than a regiment" while "consisting of two or more company-, battery-, or troop-sized units and a headquarters." The standard NATO symbol for a battalion consists of a pair of vertical lines placed above a framed unit icon. Member nations have stipulated the different names they will use for organizations of this size.

British Army

The term ''battalion'' is used in the British Army Infantry and some corps including the Royal Electrical and Mechanical Engineers, and Intelligence Corps. It was formerly used in the Royal Engineers (before they switched to regiments), and was also used in the now defunct Royal Army Ordnance Corps and Royal Pioneer Corps. Other corps usually use the term "regiment" instead.

An infantry battalion is numbered ordinarily within its regiment (e.g., 1st Battalion, The Rifles, usually referred to as 1 Rifles). It normally has a headquarters company, support company, and three rifle companies (usually, but not always, A, B and C companies). Each company is commanded by a major, the officer commanding (OC), with a captain or senior lieutenant as second-in-command (2IC). The HQ company contains signals, quartermaster, catering, intelligence, administration, pay, training, operations and medical elements. The support company usually contains anti-tank, machine gun, mortar, pioneer and reconnaissance platoons. Mechanised units usually have an attached light aid detachment (LAD) of the Royal Electrical and Mechanical Engineers (REME) to perform field repairs on vehicles and equipment. A British battalion in theatre during World War II had around 845 men; as of 2012, a British battalion had around 650 soldiers. With successive rounds of cutbacks after the war, many infantry regiments were reduced to a single battalion (others were amalgamated to form large regiments that maintained multiple battalions, e.g., the Royal Anglian Regiment).

Important figures in a battalion headquarters include:
* Commanding officer (CO) (invariably a lieutenant colonel)
* Second-in-command (2i/c) (major)
* Adjutant (captain)
* Quartermaster (QM) (LE captain)
* Quartermaster (technical) (QM(T))
* Medical officer (MO) (Royal Army Medical Corps captain or major)
* Administrative officer (Adjutant General's Corps captain or major)
* Padre (Royal Army Chaplains Department chaplain 4th or 3rd class)
* Operations officer (Ops) (lieutenant)
* Intelligence officer (IO) (lieutenant or captain)
* Regimental Signals officer (RSO) (Royal Corps of Signals captain)
* Regimental sergeant major (RSM) (warrant officer class 1)
* Regimental quartermaster sergeant (RQMS) (warrant officer class 2)
* Regimental quartermaster sergeant (technical) (RQMS(T)) (warrant officer class 2)
Battalions of other corps are given separate cardinal numbers within their corps (e.g., 101 Battalion REME).

Battle group

A battle group consists of an infantry battalion or armoured regiment with sub-units detached from other military units acting under the command of the battalion commander.

Canadian Army

In the Canadian Army, the battalion is the standard unit organization for infantry and combat service support and each battalion is divided into one or more sub-units referred to as companies.
In the Canadian Forces, most battalions are reserve units of between 100 and 200 soldiers that include an operationally ready, field-deployable component of approximately a half-company apiece. The nine regular force infantry battalions each contain three or four rifle companies and one or two support companies. Canadian battalions are generally commanded by lieutenant-colonels, though smaller reserve battalions may be commanded by majors.

Those regiments consisting of more than one battalion are:
* The Royal Canadian Regiment (three regular and one reserve battalions)
* Princess Patricia's Canadian Light Infantry (three regular battalions)
* Royal 22^e Régiment (three regular and two reserve battalions)
* The Royal Newfoundland Regiment (two reserve battalions)
Tactically, the Canadian battalion forms the core of the infantry battle group, which also includes various supporting elements such as armour, artillery, combat engineers and combat service support. An infantry battle group will typically be commanded by the commander of the core infantry battalion around which it is formed and can range in size from 300 to 1,500 or more soldiers, depending on the nature of the mission assigned.

Indian Army

A battalion in the Indian Army consists of four rifle companies. In turn each rifle company consists three platoons. A battalion in the Indian Army is commanded by a colonel. Normally a battalion is attached to a regiment of infantry, which is organized, as a general rule, of a number of battalions and the regimental centre battalion.

Royal Netherlands Army

In the Royal Netherlands Army, a mechanised infantry battalion usually consists of one command- and medical company, three mechanised infantry companies, and one support company, which has three platoons with heavy mortars and three platoons with anti-tank missiles (TOW). With the Dutch