Order of battle of an
armed force
A military, also known collectively as armed forces, is a heavily Weapon, armed, highly organized force primarily intended for warfare. Militaries are typically authorized and maintained by a sovereign state, with their members identifiable ...
participating in a military operation or campaign shows the hierarchical organization,
command structure, strength, disposition of personnel, and equipment of units and formations of the armed force. Various abbreviations are in use, including OOB, O/B, or OB, while ORBAT remains the most common in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...
. An order of battle is distinct from a
table of organisation, which is the intended composition of a given unit or formation according to the
military doctrine
Military doctrine is the expression of how military forces contribute to campaigns, major operations, battles, and engagements. A military doctrine outlines what military means should be used, how forces should be structured, where forces shou ...
of its armed force. Historically, an order of battle was the order in which troops were positioned relative to the position of the army commander or the chronological order in which ships were deployed in naval situations.
As combat operations develop during a campaign, orders of battle may be revised and altered in response to the military needs and challenges. Also the known details of an order of battle may change during the course of executing the commanders'
after action reports and/or other accounting methods (e.g. despatches) as
combat assessment is conducted.
Historical approaches

In its original form during the
Medieval
In the history of Europe, the Middle Ages or medieval period lasted approximately from the 5th to the late 15th centuries, similarly to the post-classical period of World history (field), global history. It began with the fall of the West ...
period of European warfare, an order of battle was the order in which troops were positioned relative to the position of the army commander. The term was also applied to the disposition of ships in the
line of battle during the
age of sail
The Age of Sail is a period in European history that lasted at the latest from the mid-16th (or mid-15th) to the mid-19th centuries, in which the dominance of sailing ships in global trade and warfare culminated, particularly marked by the int ...
. In the later transformation of its meaning during the European period of
Early Modern warfare the order of battle came to mean the order in which the units manoeuvered or deployed onto the battlefield to form
battle-lines, with the positioning on the right considered the place of greatest honour. This need to reflect the unit seniority led to the keeping of military staff records, in tabular form reflecting the compilation of units an army, their commanders, equipment, and locations on the battlefield.
During the
Napoleonic wars
{{Infobox military conflict
, conflict = Napoleonic Wars
, partof = the French Revolutionary and Napoleonic Wars
, image = Napoleonic Wars (revision).jpg
, caption = Left to right, top to bottom:Battl ...
the meaning of the order of battle changed yet again to reflect the changes in the composition of opposing forces during the battle owing to use of larger formations than in the previous century.
Napoleon
Napoleon Bonaparte (born Napoleone di Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French general and statesman who rose to prominence during the French Revolution and led Military career ...
also instituted the staff procedure of maintaining accurate information about the composition of the enemy order of battle, and tables of organisation, and this later evolved into an important function and an organisational tool used by
military intelligence
Military intelligence is a military discipline that uses information collection and analysis List of intelligence gathering disciplines, approaches to provide guidance and direction to assist Commanding officer, commanders in decision making pr ...
to analyse enemy capability for combat.
British historical approach
British military history is the source of some of the earliest orders of battle in the English language, and due to the British Empire's involvement in global conflicts over several centuries the records of historical orders of battle provide a valuable source of study for understanding not only of the composition, but also of tactics and doctrines of the forces through their depiction in the orders of battle. The
British Army
The British Army is the principal Army, land warfare force of the United Kingdom. the British Army comprises 73,847 regular full-time personnel, 4,127 Brigade of Gurkhas, Gurkhas, 25,742 Army Reserve (United Kingdom), volunteer reserve perso ...
and UK forces use the
acronym
An acronym is a type of abbreviation consisting of a phrase whose only pronounced elements are the initial letters or initial sounds of words inside that phrase. Acronyms are often spelled with the initial Letter (alphabet), letter of each wor ...
ORBAT to describe the structure of both friendly and enemy forces.
Operation Quicksilver, part of the British deception plan for the
Invasion of Normandy in
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
, fed German intelligence a combination of true and false information about troop deployments in Britain, causing the Germans to deduce an order of battle which suggested an invasion at the
Pas-de-Calais
The Pas-de-Calais (, ' strait of Calais'; ; ) is a department in northern France named after the French designation of the Strait of Dover, which it borders. It has the most communes of all the departments of France, with 890, and is the ...
instead of Normandy.
Clausewitz
Clausewitz defined the 'order of battle' as "that division and formation of the different arms into separate parts, or sections, of the whole Army, and that form of general position or disposition of those parts which is to be the norm throughout the whole campaign or war."
*Division comes from the permanent peacetime organization of the Army, with certain parts such as battalions, squadrons, and batteries being formed into units of higher order up to the highest of all, the whole Army.
*Disposition comes from the tactics and how these troops are to be drawn up for the battle.
Normally these tactics are exercised in peace and cannot be essentially modified when war breaks out. Order of battle belongs more to tactics than strategy. Clausewitz also noted that the order of battle depends on the effective span of control by a commander. Too few subunits makes an army unwieldy; too many subunits makes the 'power of the superior will' weak; and in addition every step by which an order has to pass weakens its effect by loss of force and longer time of transmission. Clausewitz recommended that armies have no more than eight to ten subunits and subordinate corps four to six subunits.
[Clausewitz, pp. 272-276.]
United States Army
In
United States Army
The United States Army (USA) is the primary Land warfare, land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of th ...
standing operating procedures, an order of battle to be used for operations planning should relate what an Army unit might be expected to encounter while deployed in the field. The templating of the
OoB during
maneuvers is typically the responsibility of a
battalion
A battalion is a military unit, typically consisting of up to one thousand soldiers. A battalion is commanded by a lieutenant colonel and subdivided into several Company (military unit), companies, each typically commanded by a Major (rank), ...
or
brigade
A brigade is a major tactical military unit, military formation that typically comprises three to six battalions plus supporting elements. It is roughly equivalent to an enlarged or reinforced regiment. Two or more brigades may constitute ...
commander, conducted through their
Headquarters
Headquarters (often referred to as HQ) notes the location where most or all of the important functions of an organization are coordinated. The term is used in a wide variety of situations, including private sector corporations, non-profits, mil ...
S-2 (intelligence) sections. Observations about enemy troop movements may be gathered by various military intelligence resources from all echelons, including the employment of any attached special forces units (such as
Rangers or
LRS teams) as well as
Cavalry
Historically, cavalry (from the French word ''cavalerie'', itself derived from ''cheval'' meaning "horse") are groups of soldiers or warriors who Horses in warfare, fight mounted on horseback. Until the 20th century, cavalry were the most mob ...
RSTA squadrons.
From such intelligence data, the OOB section staff compiles a likely order of battle for a
planning document or
operations order by assessing the following factors:
Enemy's Composition, Disposition, Strength (often mnemonicized with SALUTE: Size, Activity, Location, Unit, Time, Equipment):
* Composition: the command structure and organisation of headquarters and subunits
* Disposition: geographical locations of unit headquarters and subunits
* Strength expressed in units and weight of fire delivered by its weapon systems
Enemy capabilities and limitations (often mnemonicized with DRAWD: Defend, Reinforce, Attack, Withdraw, Delay):
* Personnel
training
Training is teaching, or developing in oneself or others, any skills and knowledge or fitness that relate to specific useful competencies. Training has specific goals of improving one's capability, capacity, productivity and performance. I ...
*
Logistics
Logistics is the part of supply chain management that deals with the efficient forward and reverse flow of goods, services, and related information from the point of origin to the Consumption (economics), point of consumption according to the ...
: how the enemy unit obtains its supplies and
lines of communication
* Combat Effectiveness using complex
algorithm
In mathematics and computer science, an algorithm () is a finite sequence of Rigour#Mathematics, mathematically rigorous instructions, typically used to solve a class of specific Computational problem, problems or to perform a computation. Algo ...
s and
combat modelling applications
* Electronic Technical Data used to provide data for the combat modelling applications
Enemy's Most Likely Course of Action (EMLCOA):
*
Tactics used by the enemy unit
* Miscellaneous data related to specific task, mission or operations
:* Personalities (known enemy personnel and their behaviour, often based on communications intelligence analysis)
:* Unit history used to judge expected performance based on its past performance
:* Uniforms and insignia to enable confirmation of the above data
A general rule in American military doctrine is that each unit should keep track of enemy subunits two echelons below its own: that is, a
division should monitor enemy units confronting it down to the battalion, a brigade should monitor enemy units down to
companies
A company, abbreviated as co., is a legal entity representing an association of legal people, whether natural, juridical or a mixture of both, with a specific objective. Company members share a common purpose and unite to achieve specifi ...
, and a battalion should monitor enemy forces down to
platoon
A platoon is a Military organization, military unit typically composed of two to four squads, Section (military unit), sections, or patrols. Platoon organization varies depending on the country and the Military branch, branch, but a platoon can ...
s.
The United States military's intelligence capabilities in the 21st century have allowed for monitoring even further than two echelons down the
chain of command. This
situational awareness
Situational awareness or situation awareness, often abbreviated as SA is the understanding of an environment, its elements, and how it changes with respect to time or other factors. It is also defined as the perception of the elements in the envi ...
provides a more complete picture of the
battlespace
Battlespace or battle-space is a term used to signify a military strategy which integrates multiple armed forces for the military theater (warfare), theatre of operations, including aerial warfare, air, information warfare, information, ground w ...
for both
combatant commanders and tactical commanders.
Up until the end of the Cold War, determining realistic orders of battle was generally an orderly but extremely frustrating process for NATO. The intelligence situation for Western militaries has since been exacerbated as they continue to become engaged in operations against non-traditional enemies (
insurgents,
guerrillas, etc.) and compiling orders of battle for
irregular forces
Irregular military is any military component distinct from a country's regular armed forces, representing non-standard militant elements outside of conventional governmental backing. Irregular elements can consist of militias, private armie ...
becomes very difficult; the equivalent military intelligence output requiring an increase in acquired data and analysis effort to provide an accurate and timely picture to the commander.
Examples
An example of ORBATs in
modern warfare can be found for
German forces and
Allied forces during the
Normandy landings
The Normandy landings were the landing operations and associated airborne operations on 6 June 1944 of the Allies of World War II, Allied invasion of Normandy in Operation Overlord during the Second World War. Codenamed Operation Neptune and ...
. Other examples include the
Battle of Bình Giã during the
Vietnam War
The Vietnam War (1 November 1955 – 30 April 1975) was an armed conflict in Vietnam, Laos, and Cambodia fought between North Vietnam (Democratic Republic of Vietnam) and South Vietnam (Republic of Vietnam) and their allies. North Vietnam w ...
and the
Battle of Al Faw during the
Iraq War
The Iraq War (), also referred to as the Second Gulf War, was a prolonged conflict in Iraq lasting from 2003 to 2011. It began with 2003 invasion of Iraq, the invasion by a Multi-National Force – Iraq, United States-led coalition, which ...
.
See also
*
Electronic order of battle (EOB)
*
Five paragraph order
*
List of orders of battle
References
Sources
* Carl von Clausewitz, J. J. Graham, Jan Willem Honig. ''On War''. Contributor F. N. Maude, Barnes & Noble Publishing, 2004
External links
Worldwide military aviation OrBatsat
GlobalSecurity.orgAncient and historical Orders of BattleNetherlands Armed Forces Order of Battle, 1985World War II Armed Forces — Orders of Battle and Organizations
{{Authority control
Military intelligence