In the grim darkness of the far future, there is only war!
Human scientific and social progress have ceased; humanity is in a state of total war with hostile alien races and occult forces; and the supernatural exists, is powerful and is usually untrustworthy if not outright malevolent. There are effectively no benevolent gods or spirits in the cosmos, only daemons and evil gods, and the cults dedicated to them are proliferating. In the long run, the Imperium of Man cannot hope to defeat its enemies, so the heroes of the Imperium are not fighting for a brighter future but "raging against the dying of the light". Through constant sacrifice and toil, the Imperium delays its inevitable doom.