Imperium is the human free will's 'command' over the lower (i.e. biological) faculties.

In the science fiction novel Worlds of the Imperium by Keith Laumer, the Imperium are a race or culture that take place during a time of imperialism mimicking 18th century France; the hero, Bayard, goes after an evil dictator of another world using the Blight, an interdimensional space traveling grid.

Imperium (Warhammer 40,000), a galactic empire in the fictional Warhammer 40,000 universe.

Imperium (Traveller), a galactic empire in the fictional Traveller role-playing game universe

Imperium (album), an album by Current 93

Imperium (board game), a science fiction board wargame

Imperium (play), a play by the Austrian writer and director Götz Spielmann (Antares)

Imperium (game), a strategy play-by-mail game

Imperium (film), a TV-movie series on the Julio-Claudian Dynasty

Imperium is originally a legal concept of authority in Roman antiquity. The Latin phrase "Imperium Romanum" is usually translated as "Roman Empire"; by analogy Imperium is also applied to every empire, whether ruled by an emperor or not. Other uses include:

Imperium (song), a song by Machine Head

Imperium is the name of the head of the White Martians in the Justice League Animated series.

Imperium (novel), a 2006 novel by Robert Harris set in Ciceronian Rome.

Imperium: The Philosophy of History and Politics, a 1947 book by Francis Parker Yockey (using the pen name Ulick Varange).

Imperium, a 1993 book by the Polish journalist Ryszard Kapuściński.