In the grim darkness of the far future, there is only war.
It is the 30th Millenium, and the Imperium of Mankind has launched a Great Crusade into the greater Galaxy. It's purpose, to unite all of the lost colonies of mankind under the banner of the Emperor of Man.
At the speartip of this Great Crusade are the Emperor's Space Marines, organized into the mighty 20 Legions of the Adeptus Astartes. Led by his gene forged sons, the Primarchs, the Imperium has brought to compliance hundreds of worlds in the name of Unity.