Stars without Number‘s Factions chapter provides a system for setting the campaign in motion; With tools for mechanically describing campaign elements and pitting them against each other.
The section on Using Factions in Your Game argues that a formal, yet simple, system to manage factions creates surprises for the GM; A lucky die roll from an underdog faction becomes a major news story in your campaign. Something that the players might be curious about.
Stars without Number describes factions with: Hit Points (HP), Force rating, Cunning rating, Wealth rating, FacCreds, XP, Homeworld, Tags, and deployed Assets. Each Faction Asset has HP, purchase cost, Attack value, Counterattack value, Type, Location, and Tech Level.
The Faction turn is something the GM resolves in between sessions. And looks to take no more than 30 minutes. During a Faction Turn, each Faction may take one type of action: Attack, Buy Asset, Change Homeworld, Expand Influence, Refit Asset, Repair Asset/Faction, Sell Asset, Seize Planet, Use Asset Ability.
Faction actions are informed by their faction goal: Military Conquest, Commercial Expansion, Intelligence Coup, Planetary Seizure, Expand Influence, Blood the Enemy, Peaceable Kingdom, Destroy the Foe, Inside Enemy Territory, Invincible Valor, and Wealth of Worlds. When a Faction achieves their goal, they gain XP.
The Faction's rating for Force determines the highest “level” Force asset they can buy.
|Security Personnel (1)||3||2||0||Military Unit||Force vs. Force 1d3+1 damage||1d4 damage||-|
|Strike Fleet (4)||8||12||4||Starship||Force vs. Force, 2d6 damage||1d8 damage||A|
|Psychic Assassins (5)||4||12||4||Special Forces||Cunning vs. Cunning 2d6+2 damage||None||S|
|A - asset can perform special action; S - asset has special feature or cost|
The above table encodes quite a bit of information. Cunning, Force, and Wealth each have about 25 different asset types.
Stars without Number provides a page detailing how PCs can interact with factions (or even run their own). And a page on example factions:
Thinly-populated worlds with limited infrastructure tend to have weak colonial governments concerned chiefly with issues of basic survival rather than expansion or intrigue.
Attributes: Force 4, Cunning 3, Wealth 1 Hit Points: 15
Assets: Guerrilla Populace/Force 2 and Saboteurs/Cunning 2
This world is the mightiest military power in the sector and leads a half-dozen neighboring worlds in a “voluntary confederation” that it ever seeks to expand.
Attributes: Force 8, Cunning 5, Wealth 7 Hit Points: 49
Assets: Space Marines/Force 7, Planetary Defenses/ Force 6, Blockade Fleet/Force 5, Extended Theater/Force 4, Pretech Manufactory/Wealth 7, Shipping Combine/Wealth 4, Tripwire Cells/ Cunning 4, Cyberninjas/Cunning 3
Closing out the chapter, Stars without Number provides an example of Faction Play.
I appreciate having an easy to adjudicate system to advance the background events of a campaign. As a GM, I would spend some time setting up the initial campaign factions. And as the campaign moves forward, these charged factions would exert their own influence on the campaign and adventures that play out at the table.
This system reminds me of a streamlined version of the AD&D 2E Birthright campaign system, and it's domain level play.