After the completion of their kick-ass capital Pandemonium, the swaggering Princes and Kings of Hell spread out across the blasted wastes of the Infernal Realm to establish their own fiefdoms, building holdfasts over thermal vents for warmth. Contrary to popular belief, much of Hell will freeze your balls off.
Although seemingly indestructible (they could reconstitute themselves from information wave alone-- structure that organizes matter), without God's aura, they became lethargic and damn hard to get off the couch.
So for a quick mana boost, they turned to eating their neighbours. Cannibalism became de rigueur and dinner invitations took on an added meaning. Finally a primitive agricultural system was established, and everyone chilled out. Importing human souls to feed upon began with the giant and ornery Nephilim, offspring of Watchers and human females.
Hell stretches out from the balmy shores of the Lake of Fire into the frozen continent of Sobor. Populated by choleric chimeras, scheming gorgons, bad-ass basilisks, scyllas, and uber-territorial dragons, it was a dangerous hood for individual demons. It had to be tamed like an unruly head of hair. Mowed. Paved.
Satan, being preoccupied with Eden and screwing God over, sent his trusted lieutenant Beelzebub 'Fly-Face' to pacify it. In his absence the First Magisterium was formed, consisting of 12 of the most powerful demons: Moloch, Dagon, Chemos, Rimmon, Thammuz, Baalim, Ashtoreth, Astarte, Izooze, Ozeroth, Orut, and Belial; Satan was the unofficial thirteenth member. These were the biggest, baddest, scenery-eating demons, and Satan wanted them were he could see 'em. Each founded a Royal House and began begating at a frightening pace; the little hellions sired then set about expanding the fief of their progenitor.
The Magisterium rashly adopted the Animus Creed, which affirmed evil as Hell's good ('Evil be Thou My Good'). This made cooperation impossible: it became screw or be screwed and all order collapsed. Servants stopped serving. Guards made off with the silverware. Thinking better of it, the decree was rescinded and the more restrained Pandemonium Creed, advocating opposition to God 'The Fascist Father', was adopted in its place.
Satan then tasked favoured demons to travel to earth and set themselves up as false gods and engage in the Eternal Psychomachy; members of the Magisterium were allotted the Holy Lands, where they cheekily had their temples built next to Yahweh's. They made catcalls, threw fruit, wrote obscene graffiti, drank too much, and generally stirred shit up and lowered real estate values. They also passed knowledge on to man, much to the consternation of God, who didn't like a bunch of gaudily dressed posers loitering on his turf, passing out memetic firecrackers to mischievous little kids who didn't know better.
When the temples of the false gods were finally thrown down, indescribable rage swept through the Magisterium, and Beelzebub launched a rebellion, blaming Satan for letting the indignity happen. Really he was just pissed at not being included in the Magisterium. Many demon aristocrats and their legions joined him, including Rimmon and Basher Thammuz, who were unhappy with Satan being a such prick all the time and not sharing the tastiest souls or his 10,000 succulent succubi harem.
Reinforced by huge, castle-crushing beasts from the wastelands, Beeze and company waged a thirty year war against Satan's high-handed rule, a war which weakened the empyrean essence of everyone involved. For the first time, weaker demons could be permanently dissipated. Rubbed out, in other words. Vaporized. Killed. Scrubbed.
The war ended with Beelzebub's defeat by Abaddon and 'Mofo' Moloch. His fortress of gold and iron, Beelzegrond, was razed to the ground and Beelzebub fled back into the wastelands, where it is said he was murdered by his sons, who were understandably displeased with having a loser for a dad. Satan declared the House of Beelzebub a criminal organization; members were sentenced to death. Contests were held to come up with new, innovative, and extremely painful means of execution for them.
During this turbulent period the main political factions of Hell crystallized. They complicate loyalties within the Major Houses, as no house aligns with them perfectly; Satanists are an obvious exception to this, being a one-note personality cult.
Levellers believe no spirit should ever be elevated over any other, a direct refutation of the apotheosis of The Little Enemy (Jesus). Leveller doctrine asserts the state should be organized in a non-hierarchial way. They spend a lot of their time arguing.
The Anarchists reject all order as inherently calcifying, and were banished to the outer wastelands for being a constant pain-in-the-ass; the Magisterium wanted to keep them away from Chaos and Night, their natural patrons.
Builders, led by Mulciber, work towards remaking Hell into a Paradise. 'Dream big or go home' is their motto. Attempts at weather control are ongoing, and Mulciber's engineers have engaged in endless large scale construction projects. They are funded by Mammon, the Grand Treasurer. They're annoyingly optimistic in outlook: they see a glass half full as an ocean in the making.
The Hydra Ascendant advocate open warfare with Heaven, and reject all compromise, and spend a lot of their time in bars picking fights. Not big on negotiation.
The NOM (Non-Overlapping Magisterium) faction, led by Belial, believe that Heaven, Hell, and Earth should each be left to their own devices, and not interfere in the internal affairs of others. Just screw those you've already got dominion over. Tend to file lots of protest letters.
Miscegenists advocate gradual integration of demons with humanity through interbreeding, thus making mankind indistinguishable from the Fallen Angels. Certain to piss of the Big Guy, and a lot of fun in the interim. Picky about their membership.
Animists hold true to the original Animus Creed, and reject any concept of loyalty, honour, integrity, or altruism, even between demons. They are, justifiably, trusted by no one and rarely get invited to parties. Have trouble getting organized as their meetings inevitably descend into murderous brawls.
The Limitless believe that they were created by Divine Will, and as such everything they do is Divinely Sanctioned. They tolerate no limits on their wants or needs, and naturally attract lots of divas and celebrities.
During the Harrowing of Hell, Satan denied Moloch's request to unleash his teeth gnashing legions upon The Little Enemy. Peeved, Moloch resigned as Marshall of the Infernal Armies, and began to secretly plot to bring about Armageddon prematurely by kidnapping the Anti-Christ and transporting him to earth in 1000 AD. Many members of the military, particularly Abaddon and the officer corps, supported him.
They marched upon the Gates of Hell, but were stopped by the Garrison, and were forced to lay siege. In the meantime, Satan raised a vast army to oppose the rebels, calling them 'a bunch of idiotic Upist douchebags'. The threat in the rear forced Moloch to march upon Pandemonium. He was defeated at the Battle of the Styx and sentenced to be diced for all eternity; Abaddon was cast into a pit with his followers, not to be released until Judgement Day, by which time he'd be ready to break lots of stuff.
The Third Civil War came about when three demons, Ozeroth, Orut, and Izooze, formed a Supreme Triumvirate within the Magisterium. They claimed Satan had become incapable of governing, being morbidly obese, immobile, and senile. Some said Satan had also developed Tourettes, although he may have just been pissed at being stuck in the ice of the Cocytus.
Satan, however, was not as senile as he seemed, and used his influence to start a mass counter-movement using teenage demon zealots. He founded the Lightbringers, an organization dedicated to proselytizing in his name, spreading the Satanic Shizz, and loyal to him above all else.
On Satan's instructions, The Watchers initiated an inquisition against supposed Heavenly agents, who were coincidentally found among followers of the Triumverate. Coincidence? Not likely.
This era became known as The Great Cull, which lasted from 1467 to 1583 AD. During it, over 88,881,440 demons were killed, either in mass purges or open warfare with the Armies of the Triumverate. A host of new memes and hideous abominations were created out of the fevered nightmares of twisted demonic minds and unleashed without thought of consequence upon all of Hell.
The Fall of the Triumverate was closely followed by the execution of Droogas 'The Dread', the Grand Inquisitor, and the establishment of a new Magisterium, composed of a bunch of pussified puppets closely controlled by Satan. It would be periodically purged as members grew too powerful, or developed a spine.
Satan currently is tended to by Boormoth, his obsequious Supreme Secretary and Official Archivist, who controls all his appointments and often interprets Satan's half-conscious, obscene mumblings.
Recently a heretical text called 'The Revolution Betrayed' has appeared, which claims Satan abandoned the noble principles of freedom and self-determination upon which the revolution was founded. Various demons have unjustly been connected to it by Satan, and each destroyed in turn. Some say Satan wrote the thing to discredit his enemies.
Demons survive mostly on the effluvia of human souls, a kind of 'soul dandruff', which is made into bread or used to fertilize the revolting, mana imbued crop fields; souls are also consumed directly. This manner of ingestion is strictly rationed, as it interferes with prescribed punishments. The soul's divine spark remains intact, and is soon excreted in an understandably unpleasant form (ie. shit, from solid to semi-liquid), whereupon regeneration quickly takes place. The experience is said to be highly disconcerting.
Demon Sheppards, professionals who tend The Damned, are confined to their ledge or bolgia, allowing the easier return of souls to their respective punishment zones by Human Resources post-excretion. Senior demons are much more mobile, and are often accompanied by Human Resources staff or freelance bounty hunters who pick up the waste material and see to it being returned to the proper Punishment Zone.
Different sins have different tastes, and many demons have grown fond (or sick) of certain flavours, or even specific individuals. Fast Soul Fry cooks specialize in creating dishes out of The Damned, but dishes must be served immediately, lest the soul regenerate and undo the fine cooking.
Satan himself has grown insatiably fond of traitors, who are akin to fatty comfort food, and has grown vast and obese on a steady diet of them in order to mitigate his melancholy. They have played a big part in expanding his wasteline and permanently wedging him into the ice of the Cocytus, which is now littered with tons of wrappers, cups, plates, pizza crusts, and bones.