Imperial Army

Peleliu

Banded Mongoose
Starting a thread on the Imperial Army. I thought Geir's comment in the Marine thread deserved a bit more attention:

I know this is not OTU, but I always found the idea of the Imperial Army unworkable and assumed the Imperial Marines were the Third Imperium's ground combat arm, with local worlds responsible for all Army (as in the career and the organization) units and very few of them ever deployed off their homeworlds.

In that case, it makes sense that the Marines have all of the combat arms, because even long term deployments under Imperial authority and offworld fighting in wars was all Marines. But that's just me.

My vision of the Imperial Army is that it is similar to the c.19th-early 20th century British Army (post Cardwell reforms). A regimental system based on battalions. A regiment would be composed of anything between 1 and X number of battalions. For example, the London Regiment during for WW1 was expanded to 88 battalions. The regiment is the home administrative formation. Battalions are the actual building blocks of the brigades.

Add in the complexities of melding the British Army with the Indian Army and things get interesting. Take an "average" Indian division in WW2. It was generally composed of 3 infantry brigades each of 3-5 battalions. Each brigade was "stiffened" with one British battalion with the remainder being Indian Army. Artillery, armor and other support (often British units) filled out the division. Individual battalions were frequently moved in and out of a division, but the brigade and divisional structure remained stable.

Such a system begins to looks very much like the 3rd Imperium.

IMTU Imperial Army brigades are formed of 2-5 battalions. Each brigade has one battalion of Imperial Army troops. The remainder are battalions drawn from the armies of member worlds. Brigade and higher headquarters are usually from a permanent Imperial Army command-support cadre. Especially large or wealthy worlds are sometimes permitted to field an intact brigade under their own officers, but this is generally frowned upon. Typically, individual battalions are spread out as much as possible and can be plugged into brigades operating a subsector or more apart. All troops use standard Imperial Army uniforms when in Imperial service. Patches, badges, distinctive uniform accessories, vehicle flashes, etc. identify individual units.

Imperial Marine organization differs at this level. The regiments are not just administrative units, but combat formations. A Marine regiment is a fixed triangular organization of 3 line battalions per regiment. Each regiment also includes substantial heavy support assets controlled by the regimental commander and distributed as needed. In general, Marine battalions are somewhat larger and include more integrated support units than army battalions. Nevertheless, the army always notes that Marine regiments are just brigades by a different name. Marines see a sharp distinction between the two.

On the very rare occasions the navy needs to form large formations for ground combat, they follow the army brigade structure. A naval brigade is a frightening sight to behold. And one best avoided under all but the most desperate circumstances.
 
The Army comes in divisions and armies, or even army groups.

Training and equipping soldiers isn't all that difficult, it's just transporting them interstellar that's very expensive. Even a mid-pop world can easily mobilise millions of men, so to put boots on the ground takes a lot of boots...

If you want to have a large army at the beginning of the war you use the tested and true German-French conscription-reserve system.


The Marines invaded a few badly supplied small islands far away from anything, the combined armies of Britain, Canada, and the US were needed to invade Festung Europa, and would have been needed to invade the Home Islands.

By comparison, the Imperial Marines might invade a few low pop worlds, but the Army is needed to invade, and keep, any mid-high pop world, i.e. the ones that matter.
 
As always go back to the source and see what you can learn before looking at the ideas of others.
The boardgames Fifth Frontier War and Invasion: Earth give you an overview of Imperial Army TL and unit formations - more on this in a later post,

We are told in LBB:6 Scouts

The Imperium has three "services"
The Imperial Interstellar Scout Service is a major service within the Imperium.
equal in stature to the Imperial Army and the Imperial Navy,
The major services are thus defined as
Scouts = Army = Navy
whereas the Imperial Star Marines amongst others are a minor service.

From this we infer that there are regular army formations, and that they are held in the same regard as the IN and IISS.

So where do we find their major barracks?

lmperial Way Station. A base established for the repair, maintenance, and
overhaul of lmperial equipment. It may include provisions for Army troop
barracks, naval and scout ship overhauls, and intelligence operations.

Within the Spinward Marches there are six of these:
Mirriam (Five Sisters), Flammarion (Sword Worlds), Efate (Regina), Persephone (Lunion), Junidy (Aramis), Katarulu (Trin's veil)
 
By Invasion: Earth the Imperium invaded with about 4000 btns (of which ~50 btns of Marines).

At a rough 1000 combat troops per btn, that is 4 million combat troops, and perhaps 2-3 times as many total troops?

That is very roughly 10 million people in the initial invasion...
 
By JTAS#10, a high-pop, high-tech world might have 50-100 thousand battalions, of which about a thousand are capable of off-world deployment.

That means something like 100 million combat troops of which perhaps 1 million are off-world capable.

Out of tens of billions of total population that is still less than 0.1% of the population.
 
By JTAS#10, a high-pop, high-tech world might have 50-100 thousand battalions, of which about a thousand are capable of off-world deployment.

That means something like 100 million combat troops of which perhaps 1 million are off-world capable.

Out of tens of billions of total population that is still less than 0.1% of the population.
With ~300 such worlds in the Imperium, we might see something like a total of ~10 billion combat troops, of which a few hundred million are off-world capable.

But that are the colonial troops, the true Imperial Army is presumably in addition to this?
 
In order to subdue any such world, rebellious or foreign, the Imperial Army would need at least in the region of 100 million combat troops per Domain.

The domain would also need well over 1000 Mt of J-4 transports to get them to the fight. Perhaps 1000 division-sized transports of 200 kDt each per sector?


The Imperium is big, any total numbers get ridiculous...
 
I'll repost my earlier post from the Small Craft and Marines Thread, as it is directly relevant to the discussion:

"I think the GT: Ground Forces model of the "Unified Armies of the Imperium" . . . [suggests] that the Imperium uses something akin to the "Regimental System", wherein the majority military forces scattered across the Imperium are in fact local "Planetary Defense Forces" [ = "Colonial Army" ] of individual worlds, but that each member-world of sufficient population raises one or more Regiments from its own forces to be trained-up to an "Imperial Standard" as an "Imperial Regiment" or Regiments for off-world deployment, trained by the core Imperial Army cadre. Thus individual worlds recruit for the Imperial Army through their own local "Imperial" Regimental organizations with their own local unit traditions, names, and types. That gives the "Imperial Army" a lot more local flavour and colour (and a lot more opportunity for players of former Army characters to come up with colourful unit backgrounds)."​
 
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Thr Marines are the assault force. The Navy comes in, smashes a beachhead for the Marines to take, and then the Marines hold it long enough for the Army to show up, kick ass and take names.
 
Umm, no.

How many marine units were used for the invasions of Sicily or Normandy?

The Imperial Star Marines are more akin to naval infantry with special operations capability, the Imperial Army are the heavy weights, they offer greater numbers and heavier weaponry.
 
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We could assume that the Marines are basically island hoppers; you identify a key target you want under your control, and they go and secure it.

Normandy wasn't actually a secret from the Germans, and you needed mass to take those objectives, though they did get fooled as to the primary ones.

Iwo Jima probably is about as close as you get to a large undertaking, compact, densely defended.
 
My take on the Imperial Army is from Doug Berry's [RIP] EXCELLENT GT: Ground Forces.
I myself am a US Army veteran and I have USMC and RM friends who all agree that his presentation is the most reasonable of deploying ground forces in an interstellar war.
I'll summarize:
- The Imperial Army consists of battalions donated to Imperial missions by their homeworlds. Worlds of Pop 6 or more [millions of inhabitants] are required to donate troops in proportion to their population.
- The Imperial Army is equipped with combat armor, Gauss rifles, and laser rifles. Support weapons are a mix of Gauss Support Gun, Tac Missiles, or the PGMP-13.
- All Imperial Army troops are trained to operate in zero-G, vacuum, and non-breathable atmospheres. Those battalions rated as Protected Forces ['Protec qualified'] specialize in adverse conditions to Imperial Marine levels of training. What separates Army Protec Forces from Marines is that of equipment, doctrine, and logistical tail.
- The basic building bloc of an Imperial Army is the Lift Infantry Brigade plus supporting assets. This unit consists of 3 infantry battalions plus one support battalion. All units are grav vehicle mobile.
- Supporting assets can include grav tank units, artillery units, engineer units, civil support units, etc. These units are detached from their home brigade for the purposes of the mission and then are returned after the mission is closed out.
- At the Sector level the Imperial Army is controlled by the Sector Army Headquarters, which answers to the Sector Duke for political control. Each Sector is commanded by the Sector Marshal.
- Most operational activity occurs at the Subsector level and this level is considered the most important in this regard. Each Subsector Army is commanded by a Field Marshal who answers to a Subsector Duke if one exists.
- At all levels the Army works closely with the Imperial Navy in all matters of deployment, logistics, etc.
 
neat discussion.. the roles of each branch could be handled a number of different ways but doubt I'm alone in thinking what we really would love to see is a sourcebook on the Army and the Marines.. preferably written/researched by the same people who did give us one the best sourcebooks not just for Traveller but done for any RPG game ever as this reviewer nailed. Hopefully one is already in the works and just on the QT....
 
neat discussion.. the roles of each branch could be handled a number of different ways but doubt I'm alone in thinking what we really would love to see is a sourcebook on the Army and the Marines.. preferably written/researched by the same people who did give us one the best sourcebooks not just for Traveller but done for any RPG game ever as this reviewer nailed. Hopefully one is already in the works and just on the QT....
Well, the Imperial Army is definitely the poor cousin of the Imperial Armed Forces. While the Navy is the Sword of the Imperium, not much shine is given to its Shield.
 
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