Imperium of Man

The Imperium of Man is a fictional galactic empire that contains the vast majority of humanity in the forty-first millennium, set in the Warhammer 40,000 universe created by Games Workshop.

History of the Imperium
The Imperium was founded by the Emperor of Mankind (Master of mankind, ruler of humanity and God of the human race) at the end of the "Age of Strife", a period of anarchy, lawlessness and senseless destruction that lasted for dozens of centuries and during which all but the faintest traces of the vast, advanced galactic civilization built by men in previous eras disappeared.

However, when the warpstorms of the Age of Strife subsided, the Emperor set forth to unite mankind under his rule, turning his hordes of techno-barbaric warriors into the first superhuman Space Marines.

After having secured the scientific posts and spacedocks of Luna, along with the factories and weaponshops based on Mars, the Emperor built a warfleet with which he undertook the Great Crusade, which lasted for two centuries and ended with the formal establishment of Imperial Rule over all but the most scattered and distant human colonized worlds.

During this period, the Emperor employed his most potent soldiers, the Space Marines, and their born leaders, the Primarchs. These, coupled with the combined might of the Imperial Army/Navy (later the Imperial Guard and the Imperial Navy as separate organizations), made Mankind the preeminent force to contend with in the galaxy, as its teeming numbers fulfilled what many saw as Man's destiny to rule the galaxy.

Initially the Imperium was a secular absolute monarchy headed by the Emperor. After the Horus Heresy but before the founding of the Ecclesiarchy, the Imperium was able to survive and function well against all its threats as a feudal realm headed by the High Lords of Terra and protected by the Inquisition. Codex: Witch Hunters gives a detailed history of the Imperium, starting with the realm that the Emperor himself created, to the founding of the Ecclesiarchy 3000 years after his integration with the golden throne, and the resulting change of the Imperium from a relatively secular institution to a brutal theocracy in which citizens' rights, freedoms, and even personal happiness became seen as sins, and only suffering and death for the Emperor were now recognized as virtues. Even within the Ecclesiarchy itself, attempts at reform (though seldom successful in the long term) have only rarely been made. Most notable of these was the Age of Apostasy, in which Goge Vandire, Ecclesiarch and Lord of the Administratum, ruled a "Reign of Blood" through tactics including coercion and murder, causing a radical preacher named Sebastian Thor to lead a revolutionary movement that eventually reached Terra itself and then proceeded to lay siege to the Imperial palace. Several Space Marine Chapters, including the Ultramarines, Dark Angels, and Space Wolves, sided with Sebastian Thor during the revolt. The civil war was finally ended when Vandire was turned on and killed by his own bodyguard, the Sisters of Battle. After these events, Sebastian Thor was proclaimed Ecclesiarch, and attempted to institute a series of reforms to improve the condition of the Imperium's way of life. However, these reforms did not survive long after his eventual death, and the Imperium quickly sank back to its former societal lows, with the Ecclesiarchy again becoming an institution dedicated entirely to the abuse of power against its own followers.

The Imperium in the 41st millennium
In the 41st millennium, the Imperium is nominally ruled by the most beneficent God-Emperor of Mankind. However, since his ascension to the Golden Throne following his confrontation with Warmaster Horus, the duties of actually ruling the Imperium are carried out by the Senatorum Imperialis, and the twelve High Lords of Terra. The identities and precise responsibilities of these High Lords vary, but members include a representative of the Inquisition, the Grand Master of the Officio Assassinorum, the Master of the Administratum, the Fabricator General of the Adeptus Mechanicus, and the Ecclesiarch of the Adeptus Ministorum.

Ultimately, the High Lords are in control of the entire Imperium, and are responsible for maintaining the functioning of the Imperium through the Adeptus Terra and the Imperial Commanders. In practice, given the galactic size of the Imperium, many worlds are left to fend for themselves without any direct involvement of the central government. Indeed, on some "Imperial" worlds, the last visit from Imperial officials may be only distant history or legend.

While most of the Imperium is dystopian, the empire is so massive and sprawling that it includes countless different worlds, ranging from Neolithic jungles to polluted ecumenopoleis (Warhammer 92-3). For example Gudrun, a world mentioned in the Eisenhorn Trilogy by Dan Abnett, is similar to an idyllic 18th century Merry England, with stately manors controlling vast estates of rolling green hills studded with small villages, while Catachan is a hellish Death World filled with carnivorous plants (see Planets of Warhammer 40,000).

The Adeptus Terra
The Adeptus Terra is the enormous priesthood and bureaucracy of Earth, whose scriptoria, continent-sized archives and pilgrimage sites occupy nearly all of the holy hiveworld of Terra that is not taken up by the Sanctum Imperialis, the Emperor's own resting place. The Adeptus Terra is so immense, and operates so slowly, that whole departments of it still service agencies which no longer exist and worlds dead for thousands of years.

The Administratum
One of the more useful divisions of the Adeptus Terra is the Adeptus Administratum. This organisation's main purpose is the assessment of planetary tithes: the goods, war materials and Guard regiments each Imperial world is regularly required to provide for the Imperium. However, it has also acquired many other interplanetary organisational duties.

The Ecclesiarchy


The Adeptus Ministorum, also known as the Ministorum or Ecclesiarchy, is the Church of the God-Emperor. The Adeptus Ministorum exists to regulate the many faiths that exist throughout the vast Imperium and ensure that the values of Emperor-worship are protected from perversion, while other faiths are violently stamped out. Most versions of the Imperial faith encourage productivity ("Work is Prayer"), adherence to duty, obedience to authority, and thankfulness to the Emperor. Although the Ministorium allows for variations of the Imperial faith to flourish ("The only cult we do not abhor is that of the Emperor"), the division between heresy and pious zeal can be hair-thin and malleable to those with power.

It is worth noting that the Ecclesiarchy did not exist formally until about 3000 years after the Emperor's incarceration in the Golden Throne. Prior to this it was simply the largest and strongest of the various Emperor-cults in the Imperium, which eventually grew to absorb or destroy competing cults. Once several High Lords of Terra converted and joined this cult, it was only a matter of time before it became recognized, adopted, and eventually declared the state religion of the Imperium.

Ironically, the Emperor himself did not wish to be seen as a God, rather as a great man. In fact he abhorred religion and forbade its practice anywhere in the Imperium all the way up to the Horus Heresy. He believed that it was the power of Humanity, rather than of faith, that would allow the human race to survive in the galaxy. It's worth noting that Adeptus Mechanicus and the Adeptus Astartes are not always shown to follow this creed -- something which naturally causes tension with the intolerant Ecclesiarchy.

However there is a wide variety of source material relating the Imperial Cult, much of which is contradictory. For example the Gaunt's Ghosts series of books makes frequent use of an Imperial Saint, and one also appears in the Horus Heresy series of books. These occurrences would cast doubt upon the assertion that there is nothing to the imperial faith beyond simple dogma. The way the Space Marines of today relate to the Emperor might also be thought by many to be tantamount to worship, although it is stated they do not explicitly worship the Emperor as a god, but merely see him as a great warrior to be emulated through deeds in battle and piety.

Considering the fact that faith in the Emperor has been used multiple times in the lore as defence against Chaos, it would seem unlikely that there is absolutely nothing to the Imperial Cult's insistance on absolute devotion to the Emperor above all things.

The Departmento Munitorum
The Departmento Munitorum is the central command of the Imperial warmachine, organising the logistics of planetary tithes, troop movements and troop deployment. The Departmento is far more decentralised than the other divisions of the Adeptus Terra, establishing a presence on any world with a significant tithe-grade. Distress calls from an invaded world are processed by the Munitorum, and will be passed up the ladder of system-subsector-sector-Segmentum-Imperium HQ until a division with enough reach can raise the armies needed from neighbouring systems and respond. Thus, the harder a foe strikes at the Imperium the greater the retribution will be.

The Adeptus Mechanicus

 * See main article: Adeptus Mechanicus

The Adeptus Mechanicus, the Tech-Priests of Mars, are the engineers and technicians of the Imperium, and create most of the Imperium's more advanced machinery and weaponry, build and maintain the Titan Legions and so on, despite the fact that their understanding of the technology they use is limited at best, with much of their procedure based on ritual and religious dogma rather than genuine engineering or mechanical skill. They are in effect a political entity by themselves, containing their own hierarchy of laws and armies.

Prior to the founding of the Imperium, the tech-priests were an independent entity unto themselves, and had already settled various worlds throughout the galaxy with seed worlds of their own planned Empire. Their alliance with the Emperor was dictated by their own religious doctrines in which the Emperor occupies a messianic position of authority.

The Inquisition

 * See main article: Inquisition

Independent of the rest of the Adeptus Terra are the Holy Orders of the Emperor's Inquisition. They are the ultimate judicial and police authority in the Imperium, second only to the Emperor himself.

Officio Assassinorum

 * See main article: Officio Assassinorum

An inconspicuous but vital part of the Imperial machinery of war, the Officio Assassinorum trains and deploys assassins all over the galaxy, to seek out and exterminate dangerous individuals. The deployment of one of their operatives must be sanctioned by the High Lords of Terra. In times of war (which is constant), assassins are typically deployed under the watchful eye and nominal command of an Inquisitor.

The Imperial Commanders
In addition to the Adeptus Terra and the militaries, the High Lords also command the Segmentum Commanders, who each oversee one of the five galactic regions known as the Segmentae Majoris: Segmentum Solar, Segmentum Pacificus, Segmentum Obscurus, Segmentum Tempestus and Ultima Segmentum. Each Segmentum Commander oversees his sector Commanders, who in turn oversee subsector Commanders, who oversee Imperial Commanders, also known as planetary governors. The higher ranks in this system are usually combined with a basic planetary governorship as well as interplanetary duties. This system is the means by which the Imperium, which is largely a confederacy, maintains control of the separate planets that make it up.

An Imperial Commander is the Imperially-instituted ruler of a world. However, because of the distances involved, and the unstable nature of Warp-based communication, Commanders generally operate nearly autonomously. This allows for quite a lot of variation between the governments of different Imperial worlds. The majority of governorships are hereditary (examples of this include Segmentum Commanders of Segmentum Tempestus and the royals of Volpone), though it is also not uncommon for a planet to have an elected Commander (such as the Electors of Tanith), a tyrant Commander who rules by force of arms, or anything in between. So long as the Commander fulfills his duties to the Imperium, his rule will generally go unquestioned by central authorities.

A rare few Commanders preside over feral or medieval worlds where the Imperium has not seen fit to introduce modern technology. These Commanders usually remain distant on orbital installations, only occasionally visiting the planet to police their subjects' physical status and their religious fervour (the twin threats of mutation and heresy are of prime importance to their Imperial authority), as well as collect the comparatively modest tithes these planets pay to the central government.

The Imperial duties of a Commander include paying the planetary tithe to the Administratum, controlling mutation, insurrections and heresy on his world and maintaining a planetary defence force capable of defending the planet in the event of invasion. The Planetary Defence Forces (abbreviated to PDF) should be able to halt attacks from most foes, or at least hold out until reinforcements arrive, which could take a period of months or even years.

A relatively small number of Imperial worlds are not ruled by a Commander, but are overseen by an alternate organisation such as the Adeptus Terra, Imperial Guard or Space Marines. These include the Forge Worlds of the Adeptus Mechanicus, whose inhabitants toil without pause to manufacture the weapons of the Emperor's armies (including Mars, Gryphonne IV, Esteban VII, Lucius, Ryza, Triplex Phall and Fortis Binary), the Cardinal worlds of the Ecclesiarchy, which are given entirely over to education and worship of the God-Emperor (Ignatius Cardinal, Ophelia VII), fortress worlds of the Imperial Guard (Cadia), and the Space Marine homeworlds (Fenris, Rynn's World, Macragge, Baal, Prometheus, Caliban, Medusa).

Forces of the Imperium
In the Warhammer 40,000 universe, the Imperium represents mankind's only hope for survival in a grim, merciless future set in the forty first millennium. The Imperium is surrounded by alien species, and is also under continual attack by the forces of Chaos, and extragalactic species such as the Tyranids.

The Imperium's defence forces consist of the: The forces of the Inquisition have absolute authority to combat enemies both within and outside the Imperium. Most inquisitors belong to one of three orders:
 * Imperial Guard
 * Numerous Planetary Defence Forces
 * Imperial Navy
 * Adeptus Astartes
 * Adeptus Custodes, the Emperor's bodyguard
 * Adeptus Arbites
 * Adepta Sororitas (The Adepta does not commit all of their forces in the service of the inquisition)
 * The Ordo Malleus, or Daemonhunters, including their Chamber Militant, the Grey Knights
 * The Ordo Hereticus, or Witch Hunters, including their Chamber Militant, the Adepta Sororitas
 * The Ordo Xenos, or Alien Hunters, including their Chamber Militant, the Deathwatch Space Marines

The Adeptus Mechanicus also contribute to the defense of the Imperium
 * Titan Legions
 * Skitarii

Together, these help defend the Imperium from various enemies, which include:
 * The foul forces of Chaos
 * The Dark Eldar and sometimes Eldar
 * The Tyranid Hive Fleets
 * The various Ork 'Waaagh!'s
 * The Tau Empire
 * The Necrons

Background to the Imperium in other Science Fiction
The Imperium itself, keeping with the dystopian themes of Warhammer 40,000 is a highly oppressive techno-theocracy similar to the Empire of Man found in Frank Herbert's Dune. It also resembles Asimov's Galactic Empire in the Foundation Series, with millions of star systems only loosely connected with the governing center, where technology is becoming a myth rather than a science, with extreme persecution of those questioning the morality or validity of the endless conflicts and divine rule of the Emperor.