It is the 41st Millennium. For more than a hundred centuries the First Citizen has sat immobile on the People's Throne of Earth. He is the Master of Mankind by the will of the proletariat, and master of a million worlds by the might of his inexhaustible armies. He is a rotting carcass writhing invisibly with power from the Dark Age of Technology. He is the Eternal Revolutionary of the Union for whom a thousand souls are sacrificed every day, so that he may never truly die.

Yet even in his deathless state, the First Citizen continues his eternal vigilance. Mighty battlefleets cross the daemon-infested miasma of the Warp, the only route between distant stars, their way lit by the Astronomican, the psychic manifestation of the People's will. Vast armies give battle in his name on uncounted worlds. Greatest amongst his soldiers are the Adeptus Astartes, the Space Marines, bio-engineered super-warriors. Their comrades in arms are legion: the Revolutionary Guard and countless planetary defence forces, the ever vigilant State Security and the tech-priests of the Adeptus Mechanicus to name only a few. But for all their multitudes, they are barely enough to hold off the ever-present threat from aliens, heretics, mutants - and worse.

The Terran Union was forged in the fires of revolution, when the laborers overthrew the decadent nobility of the Empire of Man. The Empire had sought to replace the worker with the machine, leaving the proletariat without work - and without food. Led by the First Citizen, the Scion of the Workers, the Great Genius of Revolutionary Thought, the people arose and strove to create a more perfect order. The Space Marines, vanguard of the revolution, liberated the Galaxy. The Imperials were defeated, those few loyalists fleeing in advanced Arkfleets, and their counterrevolutionary machines destroyed by the tech-priests of the Adeptus Mechanicus, who themselves sought power in this new order.

But this was not to last. The Space Marines had become tyrants in their own right during their conquest of the Galaxy. Many worlds had become enslaved by the Space Marine legions. When the First Citizen found out about this, he was outraged, and ordered the liberation of these slaves. Half of the Space Marine legions complied, but the other half rebelled. Following Warmaster Horus, the First Citizen's favored son, the Traitor Legions attacked Terra. The Traitors were defeated, but at great cost - the First Citizen himself was struck down by Horus in single combat. The First Citizen was interred in the People's Throne, a massive life support system that would power the broken Astronomican. The Traitors fled to the Eye of Terror, where they gave themselves up to the Chaos gods: powerful abominations that resided within the Warp.

In the last ten thousand years, the Terran Union has become a totalitarian empire far worse than the Empire it replaced. The First Citizen is generated as a god, a claim he vehemently rejected in life. Any who do not worship the First Citizen are shot outright. One could argue that this is necessary, for the whispers of Chaos are constant, and any tolerance would allow the Chaos gods to consume entire star systems. The Union also takes a strict stance against xenos: suffer not the alien to live. The Galaxy belongs to mankind, and any alien poses a threat to man's dominance.

The Traitor Legions have formed their own loose confederation. Ironically, the Traitors have developed a strict code of conduct to prevent constant war. The Space Marines who turned against the Union dominate society, with each of the original warmasters (save Horus) ruling their own portion of the Warp. Below them are Space Marines who turned after the Horus Treason, and below them are the slaves. The Traitor Legions seek more worshipers for the Chaos gods, who would be enslaved to the Traitors.

The Empire of Man persists, although as the remaining Arkworlds that fled the burning worlds of the Revolution. The Empire still maintains the lost technology of the Dark Age of Technology, technology the Adeptus Mechanicus attempts to take on a regular basis. This technology allows the Empire to fight the Union, but they are slowly losing.

The Empire's decadence has attracted the attention of the Chaos gods, and some Arkfleets have turned to Chaos. These religious fanatics want to convert the entire galaxy to Chaos, and do so through acts of terror such as crashing entire merchant fleets into planets and sacrificing themselves to a greater daemon in the middle of a crowded city.

Then there are the xenos. Most numerous are the orks, greenskinned lizard men descended from the lizard-like aliens that once dominated the Galaxy. The greenskins populate billions of worlds in the Milky Way, and the Union has tried to exterminate them on many occasions - to no avail. The orks can be peaceful, but are savage warriors - they often eat, flay, rape and dismember their opponents. And if you are fortunate, they'd do this after you die. Ork technology is elegant-looking and manufactured according to ancient tradition, but is often not as effective as its Union counterparts.

The Tau Collective is a new alien threat. A new alien empire forged in revolution, much like the Terran Union ten thousand years before. Under the rule of the mysterious Ethereals, the Tau spread their message of the Greater Good through the force of arms. Tau technology is primitive and crude, but effective, and the Tau are fanatical warriors who care not about the casualties they incur.

A more ancient threat is the Necron shogunates. Isolated for millions of years after their defeat against the Orks, the Necrons were found by an Imperial Arkfleet and shared their technology with them. The Necrons adopted this new technology eagerly, abandoning their old, frail bodies I favor of machine bodies. The Necrons of Matsu, who were gifted with this technology, spread it to their brothers, and defeated many minor interstellar states, creating the new Necron Shogunate. This rapid expansion has taken the Union by surprise, and has given the Necrons a good dose of victory disease.

And beyond the Galaxy, a new threat inches ever closer. The Union world of Tyran was the first consumed, without warning. Named the Tyranids, this mass of ravenous monsters is encroaching on the galaxy, threatening to scour it of all life. And worse of all are signs that the Tyranids are not merely moving towards the Milky Way to eat it - they are also fleeing something.

To be a man in such times is to be one amongst untold billions. It is to live in the cruelest and most bloody regime imaginable. These are the tales of those times. Forget the power of technology and science, for so much has been forgotten, never to be re-learned. Forget the promise of progress and understanding, for in the grim darkness of the far future there is only war. There is no peace amongst the stars, only an eternity of carnage and slaughter, and the laughter of thirsting gods.