Imperium

The imperium spans the whole galaxy, a million of worlds, but not necessarily connected as the warp routes have their own laws.

It spans from Holy Terra to the furthest reaches of the Eastern fringe and the distant Halo Stars. It encompasses every type of world imaginable: blistering desert worlds, teeming worlds of unknown billions living in gargantuan hive cities, ice-locked tundra with cities formed from glaciers and cardinal planets where every building is given over to the worship of the Emperor.

The God-Emperor is the ruler of mankind, who has sat the last ten thousand years immobile on the golden throne. A machine that has kept him alive since Horus treachery, although his body is shriveled. His mind is still active and battling the forces of Chaos.

The Imperium is ruled in the Emperor's name by the Adeptus Terra and the High Lords of Terra.

The Imperium is besieged by enemies on all sides and in this world mere survival is justly hailed as victory. In an Age of war the Space Marines are the Imperium's greatest hope.