The Imperium

The Imperium is the vast interstellar Empire of Humanity. Untold trillions of Humans on over a million planets are united in worshipful service of their leader, the God-Emperor. Between worlds the Human form differs wildly, its endless diversity in mind and body lauded as crucial to their collective success. The ultimate goal of the Imperium is to fulfill the Emperor’s will: that Humanity alone rule the galaxy.


Dominant amongst the Factions of the Milky Way, but forever on the edge of annihilation, the Imperium wages constant war against its many foes. Alien life is fit only for extermination, any traitors to the Imperium are heretics that must be purged, and the dark, daemonic forces of the Warp are a threat to reality itself. The Imperium is an expansionist society where new worlds exist only to be conquered. The galaxy is hostile, and the Emperor’s domain must be protected.

Continent-sized voidships carry skyscraper-tall battle walkers to warzones that span multiple star systems. Genetically enhanced warriors pray over blessed blades and prepare plasma-spewing firearms. Unremarkable Humans are plucked from their home planets, equipped with mass-produced Las weaponry, then sent lightyears from their home to hold the line against horrific alien bioforms.

War is constant, endless, and essential to ensure the growth and protection of the Imperium, but war is also costly. The Imperium pays the price in blood, sweat, and death.


The Emperor’s war machine is ever hungry for more arms, armour, and warriors. Every aspect of the Imperium struggles to support its war effort. The workforce of an entire planet might be devoted to producing armour plating, tank treads, or the food necessary for soldiers’ rations.

Little is automated despite the advanced technology; the labour is backbreaking, the hours gruelling. Some labourers work in horrendous conditions such as polluted factories with toxic materials or alongside intensely hot forge fires. Few have more than a handful of hours to rest and fulfill their mandatory religious duties before returning to their assigned vocation. Those who falter are rebuilt with mechanical limbs and organs, or left to perish. The tremendous multitudes of the population ensure anyone can be easily replaced.

Those that do not slave under the war effort or fight in righteous battle work in the Imperium’s major organisations. Largest amongst these is the Adeptus Administratum, the bureaucracy that governs the complex star-spanning Empire of Humanity. It is a monumental, nearly impossible task, even when harnessing the reality-bending powers of the Warp.

The Warp

The Imperium can only exist on its grand scale because it makes use of the Warp, a parallel universe of raw psychic energy where daemons and the terrible Gods of Chaos dwell. To dabble with this realm in any way is inherently dangerous. Any meddling with its maddening powers can open a portal through which daemons can invade realspace, and their only desire is to corrupt and consume mortal souls.

The voidships of the Imperium use esoteric technology to enter the Warp, travelling its psychic seas and emerging lightyears from their origin swiftly. Travel at this speed would be impossible in realspace, but in the Immaterium, the impossible is possible. However this is no simple task. Ships can easily be lost in the tides of the Warp, only to emerge months, years, or decades prior to or after their intended arrival time.

Some Humans, known as Psykers, have the ability to channel the supernatural energies of the Warp to manifest psychic powers. A rare breed of Psyker called ‘Astropaths’ can communicate over the vast expanse of space, though doing so poses a risk to their soul (see Chapter 11 for more on Psykers).

Travel and communication are the two most essential aspects of building and maintaining an empire. The Imperium uses the Warp to serve these needs, bringing order and unity to its expansive reaches. Many times has this reliance on the Immaterium been proven a deadly risk — no more so than now in the Gilead System, as the Great Rift renders Warp travel and Astropathic communication impossible.

The Past

The glories of the past are shrouded in mystery, lost to time and censorship. Humanity has few reliable records; millennia-old scrolls of fading text written in half-remembered languages and ancient data stores rendered inaccessible by forgotten technology form a tenuous record. Whether what is preached now is truth or propaganda is unclear, though to question established history is a heresy punishable by death.

The Imperium believe that Humanity first took to the stars aeons ago, spreading across the galaxy using advanced machinery. United in common purpose, they created advanced technologies and tamed the stars. Despite their mechanical genius, they were ignorant of many dangers. Thus, their empire was fractured by foul sorcery and abominable artificial intelligence of their own creation.

As this vast realm shattered under civil war and the perils of the Warp, individual worlds became isolated and alone. Even Holy Terra collapsed into internecine strife. It is possible Humanity may have faded and died at this point, were it not for the rise of the God- Emperor and his unification of the Species.