Generating an NPC army.

[azmodean]

Greetings, I am running a campaign that will soon involve open warfare between several nations, and I am trying to determine the size and composition of the armies involved. I have a loose estimate of the populations of the nations involved. Does anyone know of a method and/or system that could be used to do this? Random constructive criticism would be appreciated as well. Also pointers to different forums would be helpfull if you think they would be more appropriate venues for this discussion.

Thank you in advance,
Azmodean

Assume "default" population composition as per the dmg, unless you would like to suggest an alternate system as being superior.

 

[John Q. Mayhem]

I can only tell you that running mass combat with normal D&D rules gives me a physical headache. There are, fortunately, several mass combat systems on the market. Green Ronin has a simplified mass combat system for a low-magic world in Testament, Malhavoc has Cry Havoc, there's a product called Fields of Blood that I'm told is good, and the Black Company d20 book has a mass combat system.

 

[Vaxalon]

Generally speaking, a civilized nation won't have more than 1% of its population as professional soldiers. A nation with a strong "citizen soldier" tradition can muster 20% or so of its population as a semi-professional militia. Peasant levies can take as much as 30% of the population, but if they're away from their farms for more than a month or so the country could be faced with a famine.

A tribal culture, with less ties to agriculture, can muster more troops, but they tend to be less disciplined.

As for composition, the vast majority of a civilized force will be lightly armed and armored footmen. In a world where wealth was scarce, you'd find a lot of heavy wooden shields, spears of various sorts, and either leather or scale armor (if that). Only the professional soldiers, the standing army, will have much in the way of equipment.

Horse nomads, of course, would have cavalry instead of infantry, but they'd still be light on the equipment.

 

[azmodean]

As far as the mass combat is concerned, I *think* I have a handle on it. I've been working on a "Mob" "template" inspired by this thread: http://www.enworld.org/forums/showthread.php?t=109416
It basically groups the individuals into 20'x20' blocks who are treated as single creatures of the same type as the individuals composing the block, but advanced to 16x the HD of an individual. (sans a few qualities which would be nonsensical for a group of individuals like reach, and with a few qualities added, like vunerability to area attacks)... and wow, I'm hijacking my own thread.

Back on topic, one thing I am particularly interested in is the mid- and upper- ranks of the armies involved, all I have right now is generating a loose estimate of the npcs resident in the nation via the dmg chapter on settlement composition (automated by a little app I wrote) and having 1% allocated as professional soldiers and another 15-25% "drafted" into the army. This of course needs to be biased heavily by how milataristic the nation in question is, but that's part of what I'm looking for here.

Once again, thank you for your input.