[eli5] British/Canadian military: How are soldiers organized into groups?


I’m pretty sure that Battalions have Companies, but is it regiment, battalion, company, troop, soldier?

I’ve tried looking for hierarchical charts, explainer videos, nothing is clear.

In: 1

This question is not easy to answer, because even inside the mentioned army the organization can vary wildly, depending on what kind of soldiers you are talking (navy, ground forces, air, infantry company, logistics etc). In general a company (around 100 soldiers) is the building block for the smallest military unit which can administrate itself (logistics, payment etc), while around 10 soldiers is considered the smallest size for a combat-worthy squad under one command. From there however things can be mixed almost without limits, depending on doctrine, tactics, tasks etc. in addition the numbers can be outdated fairly fast because every few years military organizations tend to be re-organized to fit new budget / political / doctrine / strategy needs. And it does not help that armies tend to re-use the same name for something very different.

– The basic philosophy is: you have a command unit (this can be of course a single person for squad, or an entire team for larger units) and then you have 2-6 sub units for the different tasks in your unit. The number of units, sub units and soldiers often depends on experience what a single commander can effectively control in combat. For a squad it was found out that around 10 (8-12) is a good compromise between firepower, mobility and command ability, and this number can be found throughout the ages in many very different types of armies, from ancient Roman armies to the Wehrmacht to modern infantry squads. Same for companies etc, as all is basically build around the humans ability to remember names, units, deployment etc. The bigger the unit (and the more sub units it has) there more likely it is that the commander does not think in “individual soldiers” but in in units (*”3rd company, 2nd platoon moves over the hill and and take the northern flank”*).

– The larger the unit, the bigger the chance that it will consists out of a command sub unit, several sub units for doing whatever the task of tat unit is, and then some support units, for logistics, transport, fire support. The numbers of soldiers can vary wildly, depending on the country, task etc, sometimes even double or triple (or be at half strength) the amount in other countries or army organizations. Companies can vary from 80 to 250 men for example.

– The larger the unit there more *different* sub units it will have, enabling more and different types of operations. While a company may be very specialized (heavy tanks vs light infantry for example), a division may consists out of infantry, artillery, tanks, transports, logistics, medical, military police and combat engineers units, all of varying sizes. For specific wars and operations then there are naval and air units added to an overall command, each of them with their own specialties, sizes etc. With that an army becomes basically a set of tools, and the commanders choose which tool to apply where and how.

A **very** rough overview would be.

The individual level, often considered the most basic building block of any larger military organization.

– Single soldier
– Squad (around 10 soldiers )
– Platoon / Troop (around 20-40 soldiers , 2-4 squads)
– Company (around 100 soldiers, 2-3 platoons).

The “I may still have an idea about the individuals under my command but not really” level:

– Battalion (around 600 soldiers, 2-4 companies)
– Regiment (around 2000 soldiers, 2-4 battalions)

The “I only star at symbols at a map” level:

– Brigade (around 5000 soldiers, 2-4 regiments )
– Division (around 10 000 to 40 000 soldiers, 2-8 brigades, the UK army has for axample 3 divisions with 4-9 brigades each)
– Corps (around 50 000 soldiers or more, 2+ divisions and other attached smaller units)

From there there are other known larger formations like army, army groups, theater groups, which can number in to the millions of soldiers … like during WW2.

[This here](https://upload.wikimedia.org/wikipedia/commons/9/92/1_UK_Division_Graphic_2021.png) is an example of the UKs 1st Division (made out of 9 brigades): The symbols represent the different types of units and their sizes (standard NATO designation, so a commander can immediately see what type of unit and how big it is).


I’ll talk about the British Infantry, but keep in mind that other type of unit won’t have the same organization, but a similar structure.

Fireteam is 4 soldier.

A section is 2 fireteam (so 8 soldiers). A Corporal is the commander of the section and the first fireteam, while a lance corporal is second in command of the section and command the 2nd fireteam.

A Platoon is 3 Sections + a command element, which include the platoon CO (a Lieutenant or Second Lieutenant) and other soldier. The exact number of soldier vary. They changed a lot of details with the Army 2020 program, but the overall organization stay the same.

A Company is an HQ element and between 3 and 4 platoons. Sometime the 4th platoon is a weapon platoon with some heavier weaponry like mortar and stuff like that. The company is commanded by a captain, but some specialist company can be lead by a Major.

A Battalion is commanded by a Lt-Colonel and usually have a HQ Company, a Support Company and 3 Infantry Companies.

A Brigade is commanded by a Brigadier and it made up of an HQ, and a certain number of Battalion. By this point, you have a lot less standardization, different unit will have differnet number of battalion, some will have specialized unit, other will have reserve unit, etc.

A Division is commanded by a Major General and again the sub unit assigned to it aren’t standardized. But they will usually have 3 or 4 combat brigade, an engineer brigade, 1 or 2 logistic brigade, sometime you will see signals, medical, artillery, air defence or intelligence. It depend on their mission and how much specialized unit they need.

Now in the army you have different type of unit : infantry, armoured, cavalry, logistic, engineer, signal, medical, etc. Some of them use different names for their unit.

For Example, instead of a Infantry Brigade, Battalion, Company structure, you will have an Engineer Group, Regiment, Squadron. Or you will have Artillery Brigade, Regiment, Battery. Why they use different name is a mix of history and different need in term of size and leadership.

Now that’s just for the Army. The Navy and Air Force have their own structure with sometime different names or same name for other meanings.