Well, that's only half true. You see, there's a whole universe of people living their lives across the galaxy, and the war-borne nature of the Imperium is a huge inconvenience to that. In this post, we're gonna take a look at the other huge organizations within the human empire and begin to understand more of the life of an average dude in an otherwise terrible setting...
This is the largest of all the organizations in the Imperium. On every planet and in every community is a massive number of Priests and Clerics. Their role is to preach the word of the God-Emperor and ensure the strength of faith in every citizen.
There may be one accepted belief in the Imperium, but there is certainly not a single, unified system. You see, the galaxy is a vast place full of humans of every possible culture and society. Some planets are 'standard' worlds with basic freedoms and simple life, while others are crowded hive worlds too polluted for anyone to live outside the massive armored tower-cities. Still other worlds are backwater feral planets with tribes of humans who see their world in 'naturalist' terms and believe more in the power of nature. It must also be noted that generations of humans are born and die in grand spaceships, moons and asteroids support colonies, and any number of other environments exist where mankind lives. All these different places must be faithful, and the priests are responsible for every soul wherever they are.
The underlying core of the Imperial Faith is that the immortal God-Emperor united all man acrss the stars and introduced them to a utopia of shared sacrifice and success. With the great powers that he wielded, he held back the invading enemies of man, from alien to witch, and freed humankind from certain extinction. Whether he did this as the Sun-God, Warrior-Avatar, or Benevolent Spirit is what makes each world's belief system vary from the next.
The Ecclesiarchy, as the Adeptus Ministorum is more commonly known, is also responsible for creating more 'local' centers of worship. Not only does this include Saints and Holy Artefacts, but they also create massive churches and cathedrals, commonly known as Basilicas. These Basilicas serve to remind the surrounding population of the power of faith, as well as housing artefacts and bodies of Saints worshipped by the people. In fact, the vast majority of migration in the Imperium is holy pilgrimages to these places. The Imperial Faith serves as a driving force for the person, a protecting force for culture, and a unifying force for the entire galactic society.
Adeptus Administratum
The second largest organization in the Imperium, this is the body responsible for the operation of the empire. It is, by far, the most non-descript of all and yet is probably the most important in the galactic sense.
To this body do the Governors and their attendant staffs belong. This is where the secretaries, librarians, bookkeepers, accountants, and all other manner of administrators belong. Each planetary lord is required to govern thousands or millions of these workers, ensuring that his world is able to provide protection for the people and supply the required tithes to the Imperial efforts.
When a noble wishes to ship goods off-world, it's the Administratum that they must see. When a civilian needs to acquire permits for work-crews or seeks records for family or business ventures, it's the Administratum they must see. This organization may not be the most efficient or fastest group, but its importance is far greater than the average person knows.
Adeptus Telepathica
This group is neither large nor well-known, but its role is vital nonethess. For millenia, the mutation that grants humans psychic powers has become more common. Here is where the darkness and light of the galaxy converge.
Some humans develop powers that are useful, while most are very dangerous to greater society. The use of psychic powers simply pulls the stuff of the Immaterium, or the Warp, into the real world. Shaping this power into effects is how the Psyker is able to manifest these abilities. Most common of all is the power to communicate across the vastness of space.
Standard communication through real-space would take thousands, or even millions, of years. The ability to send messages through the Warp allows communication to take hours, days, or weeks, but definitely increases the ability to operate a galactic empire. Mutual defense would be impossible, otherwise. The ability to travel and trade would be impossible as well. In fact, the 'Dark Age' of humankind befell because interstellar communication was impossible. Luckily, the Emperor determined the need and found the timing coincided with calmer Warp-storms and established an entire empire across the galaxy.
It should also be noted that this organization co-exists with the Inquisition and Adeptus Astronomica. While some humans develop fantastic powers, they would go unnoticed except in their societies and the need of the Imperium would go woefully unmet. The Black Ships of the Inquisition visit nearly every planet and collect all Psykers detected by that governor. Those that are found strong and able are sent to academies and trained to use their arts, where they are then assigned to planetary Administratums and even sanctioned for use by Imperial Guard regimental commanders. Those that are found weak and unable to control their powers are turned over to the Astropathic Choir, where they will be soul-fed to the Golden Throne, keeping the Emperor's body barely alive and magnifying the holy Beacon.
Finally, within this organization is the tiny body known as the Navis Nobilitae. This is the group of families that have the unique psychic mutation that creates the three-eyed navigators. This group of humans is able to 'see' in the Warp and even detect the holy Beacon, known as the Astronomicon (named after the group that feeds it). They are as secretive as the Inquisition itself, and therefore won't be discussed here.
Adeptus Arbites
Here is the organization that ensures lawlessness does not break out on planets. The Arbites are the peace-keeping force that searches for heresies, mutinites, and planetary plots of destruction and mayhem.
Although they are not 'military' as such, the Adeptus Arbites recieve better training and equipment thna the average Imperial Guard soldier. Their armor and weapons are made to withstand great amounts of punishment and give it back out. Their normal foes are as low as simple hive-ganger and as great as Renegade Governor's personal bodyguards. Toss in the occasional monsters and mutants, all too common in the massive Imperium, and the need to be so effective in combat is obvious.
Take note that the Arbites are not the same as police or constables in normal society. The Arbites are responsible for Imperial Law, enacting operations to ensure the galaxy is safe from every planet's risks to it. The Arbites' authority is derived from the High Lords themselves, allowing them to investigate the very planetary government they are there to protect. Should a Governor ever decide to become independant and renegade from the Imperium, it is the Arbites that will be his first enemy. The Adeptus Arbites are cop, judge, and executioners given form in practice and authority. In order to ensure the purity of this practice, newly-trained Arbites are always stationed to worlds sectors from their own, to ensure they are always brutal and objective when meeting out the Emperor's law.
It must be understood that each planet does still have its own law enforcement agencies. Some planets have citizen-constables, noble-supported personal militias, and even powerful family elders. The most prominent planets use Enforcers, local law-enforcement agencies that closely mirror the Adeptus Arbites. However, their realm of influence are very different, and even Enforcers are subject to the judgement of local Arbites.
Adeptus Mechanicus
This organization is special insofar as it's not officially a part of the Imperium. Little do most people know, the Emperor granted the Mechanicus freedom and autonomy in return for weapons and technology. The Imperium and Mechanicus is 'allied' for a greater cause, but they are not the same.
The Adeptus Mechanicus is the culture that grew on Mars for thousands of years before the ascension of the almighty Emperor on Terra. When he began his expansion, marching legions of steam-punk warriors into space, he found the red planet controlled by a technologically-advanced people who controlled machinery well beyond his wildest dreams. Once the inital friction between the two forces had abated, the Imperial armies were outfitted with fantastic weaponry, advanced starships, and great techonology that mankind had long since forgotten about or lost. In return for their autonomy, the Fabricator-Generals of Mars agreed to supply and upkeep this technology. For this advancment of thousands of years, the Imperium need only turn over all newfound archeotech to the Mechanicum.
Since mankind had long-since forgotten and lost all the technology they had discovered and created for 50 millenia, working machines were given a spiritual reverence. In fact, the Adeptus Mechanicus themselves imbued all technology as being holy, and their society revered the Omnissiah above all. Semi-sentient computers, blessed machinery, and holy weapons became a lifestyle and faith. So much so that the Mechanicus people seek to replace organic body parts with machinery and change their rational thinking faculties to binary, ridding themselves of the failings of the human body.
Every organization of any repute in the galaxy has Adeptus Mechanicus agents in thrall. Not only are these tech-priests necessary for the upkeep of all the gear that makes the empire operate, but their presence allows the expansion and discovery of the empire of technology. Without the Adeptus Mechanicus nearby, great war engines would never be shared across the breadth of the Imperial armies, citizens would never have the opportunity to learn how to care for their equipment, and the planetary Lords would cease to have the power over the masses that they often enjoy. Unfortunately the inhuman behaviours of the tech-priests often creates conflict and antipathy in normal humans, usually for good reason.
There are many more organizations that bear mentioning, but these are the big ones. I hope to produce another blog for them, but I'm sure that'll be far in the future. In the meantime, enjoy the universe and always feel free to let me know what you think!