It is the 41st Millenium. For ten thousand years, the Emperor has led his grear war-fleets from the Silver Throne of Luna. He is the master of mankind by the will of the sword and the storm, and master of a million worlds by the might of his indestructible armies. He is a deathless vampire, writhing visibly with the untold powers of the Red Age of Sorcery. He is the Wolf Khan of the Experium, for whom ten thousand souls are impaled every day, so that he may continue to ride out against the enemies of man.
Yet even in his deathless state, the Emperor's vigilance fades. Mighty battlefleets struggle through the demon-infested sargasso of the Immaterium, the only route between the bleeding stars, their way lit only by the baleful light of the Unblinking Eye. Vast armies battle in His name on uncounted worlds. Greatest amongst his scions are the Adeptus Cicatrix, the Scarred Marines, chaos-warped super-warriors. Their servitors and sometime foes include the Principalitans and their cults and armies, the inescapable Guild of Shadows, and the Tech-Sorcerers of the Arean Cult, to name but a few. But for all their multitudes, they can rarely hold together against the ever-present threat from aliens, traitors and marauders - or worse.
To be a man in such times is to be one amongst untold billions. It is to live in the midst of the cruelest and bloodiest war 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 dark 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.