Biography
Warhammer 40000 is name of fantasy/sci-fi universe based on original Warhammer universe and 40000 is referencing to future time as events are set in space age (compared to "medieval-like" Warhammer universe).
Songs described by this Artist are "soundtrack" to games, books and like for this fantasy universe made by various artists.
Biography text from Last.fm, available under CC BY-SA.