Warhammer 40k
"It is the 41st millenia, and their is only war." - Adeptus Astartes Librarian
Any and all games based on the Warhammer 40k setting follow the same outline for each race/faction as to who they are and what they fight for. Warhammer 40k is a Military Sci-Fi Fantasy setting where most of the Universe has been already discovered by a diversity of different races/faction.
The different factions include the Imperium of Man (Imperial Guard, Space Marines, Witch Hunters, Demon Hunters, Adeptus Arbites, and other forces of Humanity), the Eldar, the Dark Elar, the Tau Empire, the Necrons, the forces of Chaos, and the Tyranids.
Much more can be learned by reading these books:
(Warhammer 40k 5th Edition Core Rulebook)
