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Warhammer 40K Lore For Beginners (What You Need to Know)

Warhammer 40,000 isn’t just a popular tabletop wargame with miniatures and dice-rolling – it’s also a massive fictional universe that the publisher Games Workshop has been expanding on for four decades!

Every month, Games Workshop adds something to the story of Warhammer 40,000 with book or model releases, and every day, wikis and Youtube channels across the web also add new content about the history of the fictional universe to an ever-increasing body of Warhammer 40,000 lore. Needless to say, this constant stream of content can make 40k (as it’s abbreviated) lore difficult to get into as a beginner.

In this, our Warhammer 40k Lore for Beginners article, we give beginners everything they need to take their first steps into the grim, dark future of Warhammer 40,000 lore: We explain basic concepts about how the universe works, the most important factions and their history, and where the storyline has progressed to after 40 years.

Needless to say, this article will not cover everything, and there’s no doubt hardcore fans of the lore will also find that we are omitting crucial information – but this is just a primer, and we hope it will encourage you to jump off the deep end and go explore the 40k universe for yourself, whether you’re planning on playing the game, reading the novels, or just like knowing what different science fiction franchises are about.

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What genre is Warhammer 40,000?

The simplest answer is that Warhammer 40K is science fiction, and that’s also correct in many ways. Like most other science fiction worlds, it does take place in the future – the very far future, actually. It is also science fiction in the sense that much of its worldbuilding revolves around the use of technology that hasn’t been invented yet – and the moral and political consequences of the use of that technology.

That being said, 40K isn’t classical space-faring science fiction like Star Trek.

First of all, it’s deeply pessimistic and dystopian: Pretty much everything in the future of the 40K universe has gone completely wrong, and apart from a few factions and some recent plot developments, progress and enlightenment are nowhere to be found.

Secondly, technology has devolved rather than evolved in many ways in 40K (more on that in the technology section below), and if you forget the spaceships and lasers of the setting for a second, it could just as well be a dark fantasy epic about ancient heroes battling monsters, wielding legendary swords and magical powers.

What draws 40K even more in the direction of fantasy is the presence of a range of species/races that seem plucked directly from a Lord of the Rings-like fantasy novel: The heroic humans are there, of course, but so are high elves (the Asuryani Aeldari), dark elves (the Drukhari), Orcs (the Orks, simply), ogres (Ogryn), hobbits (Ratlings), dwarves (The Leagues of Votann), and even a species similar to the undead (Necrons).

All of these are a lot different than their usual medieval fantasy counterparts, though: The Aeldari are still an ancient, dwindling species, but they travel on huge spaceships full of the souls of their dead; The Votann are still smiths and artisans with a temper, but they’re also clones, the Orks of 40K don’t serve a dark overlord, but spread their brand of joyous violence across the stars nonetheless; and the Necrons are undying, unfeeling entities, but rather than occupying crumbling undead bodies, they live on in living metal that reconstructs itself upon destruction.

While 40K contains major science fiction and fantasy elements, it’s also important to know that the individual stories told within the 40K universe make up a much more diverse list of genres than just that. There are crime stories of detectives solving murders in film noir-esque megacities, farcical comedies about silly orks, classical pulp adventures aimed at young readers, gritty war stories of infantry squads fighting in the muddy trenches of endless battlefields, and – perhaps most of all – tons and tons of horror stories.

The shorthand term for the strange one of a kind genre that 40K represents is “grimdark”, a term that pretty perfectly sums up how all the genres and subgenres mentioned above are all tied together by the sheer hopelessness and terror of the 40K universe and its depiction of a future that hasn’t in any way turned out how any of us would have liked it to.

Eldar vehicle image in our article about Warhammer 40k Lore

When and where does Warhammer 40,000 take place?

40K mostly takes place around 40,000 years from now in the 41st millenium AD. It has a very important and highly detailed prelude that takes place 10,000 years before that (more on that below), and in recent years, the storyline has begun slowly creeping towards some day taking place in the 42nd millenium, but for most of 40Ks lifetime as a fictional universe, events have been happening right around the 40,000 AD timestamp.

40K takes place in our galaxy, so places like Earth (called Terra) and the Sun are in there, but the galaxy is unrecognisable in many ways. Humanity has colonized much of it, but many alien species have also claimed parts of it, and all of it is closely connected to the horrifying parallel dimension of the Immaterium or the Warp, which is a Chaos-infested realm that defies the laws of physics, letting the civilisations of the galaxy use it as a (very, very dangerous and unreliable) shortcut between destinations, so that traveling from one side of the galaxy to the other at least has a chance to go pretty quickly.

Currently, the galaxy is split in two through the “middle” by a great rift that opens up into the Warp, with our solar system and Terra on the one side, and the Imperium Nihilus, a human-controlled area with no stable contact to Terra, on the other.

What are the most important factions in Warhammer 40k Lore?

The Imperium of Mankind

The Imperium of Mankind is the civilisation that is home to most of the untold billions of humans living across the galaxy. More than 10,000 years old, the Imperium is a civilisation that is always almost at the brink of extinction due to numerous threats to its existence from without and within. The offical leader of the Imperium is the God-Emperor of Mankind – an immortal, powerful psychic warrior and genius who united humanity under his banner 10,000 years ago, but who is now little more than an artificially sustained corpse locked away deep in his palace on Terra, while he uses his powers to protect the Empire against the forces of Chaos.

In everyday life, the Imperium is actually ruled by a monstrous bureacracy of administrators, generals and priests in what can best be described as a theocratic police state where religious doctrine and mountains of paperwork keeps everything under at least some kind of control (more on that in the next section).

To defend itself from the many dangers that surround it, the Imperium has many different military and paramilitary organisations, but the two of those you have to know to understand the 40K setting are the Space Marines and the Astra Militarum.

Space Marines Boarding Patrol
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The Space Marines are a superhuman force of genetically altered and biomechanically augmented elite warriors originally created as 20 Legions with 20 different superheroic Primarch leaders by the Emperor. The Space Marines are set apart from the rest of human society. This is in part because they’re barely human:

They’re taller and stronger than ordinary humans, and also look somewhat distorted from the human form because of all their implants and extra organs (they have two hearts!), and they don’t die of old age or from most diseases, so some of them are thousands of years old.

However, their separation from the rest of humanity is also due to the sometimes pretty bizarre warrior-monastic cultures of their Space Marine Chapters: To just name a few, the Blood Angels chapter suffer from an almost vampiric disease which stems from the collective trauma of the death of their Primarch 10,000 years ago, which can drive them to go insane and enter a dangerous berserk state during battle,

The Iron Hands replace their physical limbs with mechanical augments to overcome the fragility of the human form, the Space Wolves live for glory and renown but also carry a curse that can turn them into wolf-like beasts, The Black Templars are xenophobic crusader zealots covered in religious iconography, and so on -they’re all pretty wild.

No matter how inhuman and terrifying the Space Marines may seem, they’re a big part of the reason humanity is still in the game of galactic domination, since their superhuman powers and dedication to warfare above all allow the Imperium to compete with some of the more advanced or more physically strong alien species in the galaxy.

Astra Militarum Combat Patrol
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The Astra Militarum is the other main arm of Imperial military power, and instead of betting it all on superhuman augmentation, the Astra Militarum instead finds its strength in the sheer quantity of Imperium-controlled worlds that make up the Imperium of Mankind. It is basically the human army, consisting of billions of ground troops enlisted from all across the galaxy (many planets have their own distinct military traditions which also make for a lot of fun world-building, which you can start reading about in Dan Abnett’s First and Only, for example) and of an insane amount of crude firepower in the shape of mass-produced tanks and artillery sourced from the extremely productive industry of the Imperium, all of which is pretty much geared towards producing for the military. This means that the Astra Militarum pretty closely resembles a slightly futuristic and extremely exaggerated version of a European World War I army.

There are many more subfactions within the Imperium – the Adepta Sororitas, the Mechanicum, The Ecclesiarchy and the Inquisition, just to name a few, but we’ll get back to those in the more theme-specific topics below.

The one thing that’s most important to know about the Imperium for a novice of 40K lore, however, is that, while the Imperium of Mankind, and especially the Space Marines, might be the protagonists of the 40K universe in many ways, they are not the good guys. The Imperium is an incredibly cruel, unbelievably oppressive monster of a civilisation that is horrible to its citizens and its enemies alike.

The leaders of the Imperium are very much villains in the eyes of the other species in the 40K galaxy, but can also often seem so to fans of the hobby. But: They’re also the humans of the 40K setting, which makes it natural to identify with them anyway, which is sort of what makes 40K so interesting: It forces readers/viewers/players to identify with something of which there’s nothing to be proud of, and it can make you think about how the Imperium might not be so different from some of the bad ways in which humans behave in our world today – but it’s delivered in an exaggerated, absurd and darkly satirical way that doesn’t make that message feel preachy.

The Forces of Chaos

While the citizens of the Imperium worship the God Emperor of Mankind, there are also those who chose to turn their back on him and the constraints of morality and order. Instead, they worship the Ruinous Powers, the god-like entities who populate the Warp, who in turn grant them supernatural powers, although they usually come at a great price. The Forces of Chaos are the sworn enemies of the Imperium, but also of the Aeldari and many other civilizations in the Galaxy.

Codex: Chaos Space Marines (2022)
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The Chaos Space Marine legions are remnants and descendants of Imperial Space Marine Legions who followed their Primarchs into the embrace of Chaos when they turned their back on the Emperor 10,000 years ago (we’ll expand on that in the events section below).

Like the Space Marine chapters loyal to the Emperor, they’re also superhuman warriors in power armour, but the chaos and madness of their Primarch have made each Legion’s culture stranger than even those of the loyal Space Marines: The Death Guard worship Nurgle, the Chaos God of Decay, and they walk around covered in flies, their bowels spilling out of their armour; The World Eaters worship Khorne, the Chaos God of Rage, and charge into battle with chain-axes in a rain of blood and guts, indifferent to whether the blood spilled belongs to them or their foes; The Emperor’s Children are deranged hedonists and worshippers of Slaanesh, the Chaos God of Excess, whose apothecaries have modified them with alien organs and traits so that they can kill with their screams alone, and the Thousand Sons are dust golems and arcane sorcerers worshipping Tzeentch the Chaos God of Magic and Change, just to name a couple.

And on top of those who have thrown their lot in with the Chaos Gods, some Chaos Space Marine chapters, such as the Night Lords, by-and-large avoid worshipping these rulers of the warp and instead focus on pursuing their war against the Imperium, with Terra firmly in their sights (with a little bit of infighting, plotting, and scheming against other chapters just for good measure).

They are led, to the extent that leadership makes any sense to them in their madness, by Ezekyle Abaddon of the Black Legion, a veteran of the original rebellion against the Emperor, who has sworn to bring down the Imperium once and for all.

Along with the Space Marines, deserter Traitor Guard have also left the Astra Militarum behind to fight for the favor of the Chaos Gods instead, and Daemons of Chaos, pure manifestations of the horrors of the Warp, also make incursions into the realspace of the Galaxy.

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The Xenos

The Xenos aren’t a faction in the way the Imperium or the Forces of Chaos are. Instead, Xenos is an Imperial term for everything in the galaxy that’s not of human origin. This means that the Xenos are all the highly diverse alien civilization that compete with the Imperium for space in the Galaxy. While the list of Xenos races who have their own faction in the 40K game are very limited, there are dozens of them in 40K lore, spanning from great monsters that only ever show up in one story to huge civilisations. The most important ones are:

  • The Aeldari: This ancient species of humanoids once ruled the Galaxy, but in their quest for ultimate perfection, they fell to hedonism and created the Chaos God Slaanesh who now seeks to consume the souls of all Aeldari who die. Their race is now dwindling and scattered into multiple factions. The Asuryani Aeldari try to walk a righteous path through strict self-control and dedication as they travel the galaxy in a quest to save the souls of their dead from Slaanesh, while the Drukhari revel in pain and suffering as raiders and torturers, feared across the galaxy. The Ynnari, a more recent faction of Aeldari, are trying to unite all Aeldari in an attempt at rebirth for their species through the creation of a new god of Death. The Aeldari, like the elves of Tolkienesque fantasy, are ancient and graceful, but also arrogant and sometimes ignorant of the challenges facing the short-lived humans they encounter. Aeldari are often the enemies of the Imperium (which categorically refuses to tolerate non-human species in their domain), but they also communicate with, and cooperate with, humans when the Aeldari gift of foresight shows them a path to a better future that requires cooperation.
  • The Orks: The Orks are the great green menace of the galaxy, and one of the archenemies of the Imperium, who have been fighting them for more than 10,000 years. They’re an entirely war-focused society of hulking, genderless brutes who grow bigger and more dangerous the more they fight. Nobody knows exactly where they come from or how they work, but to the outside observer it seems that they grow like fungus out of the ground, and that they are able to increase their numbers by the millions very quickly whenever they declare one of their crusade-like Waaaaagh!s against civilisations or planets. More than anything, the Orks find great joy in fighting, making them the most positive faction of 40K by a wide margin.
  • The Necrons: The Necrons are a mechanical civilisation of intelligent skeletal automatons who used to be a species of flesh and blood until they left their bodies behind in an act of biotransference to gain the upper hand in a great war eons ago. Recently, they have risen from the sarcophagi of the Tomb Worlds in untold numbers to rid the galaxy of all biological life and silence the Warp once and for all. Their insanely advanced technology renders them almost immortal, and their leaders are able to resurrect their minions from even the most severe damage. Whereever they go, life ends.
  • The T’au: The T’au rule a relatively small, but advanced and often peaceful and prosperous empire at the fringes of the Galaxy. The T’au live to serve the Greater Good communicated to them by their leaders, and they’re a sceptical, progressive and tolerant society who don’t share the xenophobic tendencies of other factions in the galaxy: They happily incorporate other species into their empires, and there are even examples of human populations joining the T’au rather than living under the boot of the Imperium. Whenever a civilisation resists the Greater Good, however, the Fire Warriors and Battlesuits of the high tech T’au show that they’re a formidable people of war as much as they are one of tolerance and progress.
  • The Tyranids: The Tyranids are the most inhuman of all Xenos: They’re a nightmarish locust swarm of biological horrors, a cloud of tentacles and teeth spreading across the galaxy, attempting to consume and integrate all biological matter into their own genepool to serve the schemes of the Hiveminds that control them. The most sinister form of their consumption of worlds takes the shape of an infestation: Tyranid Genestealers infiltrate Imperial Worlds among the working classes and breed until their offspring almost look like humans. Then, they incite revolutions and insurrections of of zealous Genestealer Cults who believe they will be saved by angels from the heavens if they overthrow the unjust governments of their homeworlds. As soon as their rebellion is close to victory, the “angels” arrive: A Tyranid Swarm that devours everything, the Cults included.
  • The Leagues of Votann: The Leagues of Votann, like the Imperium of Man, find the origin of their species on Terra/Earth, but tens of thousands of years living close to galactic core have made them short, stout and sturdy. They don’t evolve naturally, but are all cloned from various specialized clone-skeins, guided by the Votann, ancient sentient artificial intelligences whom the Leagues worship as much as ancestors as as gods. The Leagues harbor none of the suspicion towards technology that has crippled the Imperium, and while they aren’t as numerous as the humans, they are swiftly making up for it in times of war with their technological marvels of warfare such as magna-rail guns and volkite weaponry. The Leagues are a collectivistic society with a shared ancestry with humans, but with an agenda all of their own.

What is society like in Warhammer 40k lore?

While the 40K universe is mostly all about war, the various stories in novels, audio dramas and sourcebooks for the franchise do tell us a lot about how society is structured within the universe – especially in the case of the Imperium of Man. This section of the article goes into more detail with everyday life in the Imperium.

Faith and Heresy

Everyday life in the Imperium is saturated with religion in all areas of life: Utter devotion to the Emperor is expected from everyone, and religious rituals such as prayers, processions, blessings and the burning of incense are part of everything from celebrations to the operating of machinery (see below). The worship of the Emperor (and a vast array of saints) also heavily influence architecture and design in the Imperium, so that everything is constructed with spires, mosaics and angelic sculpture whereever it can fit onto a building, fortification – or even the huge spaceships traveling between the worlds of the Imperium, which look like spacefaring cathedrals. This is often referred to as the Imperium being “Space Catholic”, which should give you a good idea of the visual style.

A society so fundamentally tied up in religious dogma and practice doesn’t tolerate deviation from the true path dictated by religion. In 40K, that means that heresy is one of the greatest taboos of the Imperium, and such violations of religious doctrine are policed by the Inquisition, the various forms of police, and even by the Space Marines themselves. Since the great Chaos-fueled rebellion of the Horus Heresy, the subjects turning their back on the worship of the Emperor has been perceived as perhaps the main threat to the Imperium, and Imperial institutions spent unbelievable amounts of resources keeping that threat contained – which isn’t always easy, given the vast diversity of their subjects.

Diversity and Bureacracy

Because humanity has populated the galaxy outside of Terra for more than 20,000 years, the many human-populated worlds that make up the Imperium are incredibly diverse – not just because of their very different climates and living conditions, but also because human culture has had time to diverge in all sorts of directions before the rise of the Imperium. Some worlds are almost medieval, with knightly orders in gigantic mechanical walkers protecting farmers and serfs from dragon-like monsters. Other worlds are pock-marked by hive cities where billions of humans live under horrible conditions, surviving in gangs while manning massive industrial complexes that feed the Imperial war machine. Yet other worlds are covered in shrines and cathedrals and are the destination of galaxy-spanning pilgrimages. The level of civilization and technology on Imperial worlds vary wildly, but the Imperium has coped with this by making what holds the Imperium together pretty simple: Everyone must worship the Emperor, everyone must pay a tithe of taxes to the Imperium, and everyone must aid the Astra Militarum in fighting the enemies of Mankind. To keep track of all this, the Imperium employs a bureacracy that’s almost a religious organisation in itself, collecting tithes and trying to gather enough information about the many human worlds to make a coordinated war effort possible.

The one place where the diversity of the Imperium is most evident is, of course, in the Astra Militarum. Here, regiments from all kinds of cultures meet up to fight the enemies of Mankind. The Cadians, for example, are a warrior society through and through, because each recruit grew up guarding their world against a gigantic Chaos Incursion – until the forces of Chaos finally managed to destroy the planet. Now, they’re one of the most revered fighting forces in the Imperium, a role model for other regiments in how to never back down, their motto being “the planet broke before the Guard did”. The Death Korps of Krieg, on the other hand, are siege specialists in gas masks famous for their complete disregard for their own safety, taken to be a way of atoning for their past trangressions. The Catachan are fierce jungle fighters – and we could go on. If you want to see the breadth of the Imperium, look to its soldiers.

Mutation and Xenophobia

“Abhor the mutant” and “Suffer not the alien to live” are among the many mottos of the Imperium. Mutation is common in the Imperium, since humans evolve and are exposed to all sorts of influences across the Galaxy, and the Imperium does tolerate some strains of it, such as the superhumanly strong Ogryn who perform many important tasks in industry and military, but the essential purity of the human species is still extremely important to the Imperium, so mutants whose bodies and abilities stray too far from the baseline are hunted down and exterminated.

This is mostly due to another boundary of humanity that the Imperium polices: That between the human and the decidedly non-human, the alien. To say that the Imperium has a strained relationship with the Xenos is a huge understatement: In most cases, humans of the Imperium kill aliens on sight if they can. There are numerous exceptions, of course, the age and size of the Imperium being what it is. Aeldari have time and again served as council or temporary allies to the Imperium, but don’t maintain anything resembling a permanent alliance with Mankind, who just as often wages war against them. In some desperate situations, companies of Astra Militarum have even fought alongside Orks against Tyranids, or in some other constellation with Xenos armies, only to turn on them a second later. Finally, the Rogue Traders, a strange expeditionary force of rich nobles serving as explorers and merchants at the fringes of the Imperium, are granted the freedom to cooperate and trade with aliens whenever it furthers the cause of the Imperium.

Other societies

As described in the section above this one, there are many other societies and civilisations in the Galaxy than the Imperium: Many human worlds are ruled by the forces of Chaos rather than the Imperium, and then of course the myriad Xenos societies are just as diverse as the human ones – but like the non-human races of The Lord of the Rings, for example, they’re very much defined by how they are different from humans. The Aeldari aren’t short-lived and reliant on strength in numbers like the humans – they’re ancient and superior despite their dwindling population. The Orks aren’t organized and fragile like the humans – they’re playfully insane and insanely strong, and so on. The societies of some Xenos are more fleshed out than others in the lore: There are really good novels about Aeldari, T’au, Necrons and Orks, but not as many yet about Genestealer Cults or the Leagues of Votann.

Imperium Nihilus

So far, it seems like a pretty rough ride for many in the Imperium as a whole. But remember earlier on in this article when we mentioned that the universe has now been cut in half by a giant warp rift commonly refered to as the Cicatrix Maledictum? On the Terra side of things, life goes on much as it did before (if you ignore the so called Psychic Awakening that is making more and more humans psykers across the Imperium). On the other side however, Imperium Nihilus, hundreds of billions of human lives have been made all the tougher. When the rift first appeared, great warp storms engulfed entire planets, daemons in large numbers swarmed entire populations, and cultists rose to power – turning once loyal worlds into bastions of Chaos. In worlds that were spared the brunt of these brutal events, mutation spread rapidly through other planets, causing Imperial citizens to turn against each other in a desperate act of survival.

To combat this, worlds set up for large agricultural operations created militias to defend themselves whereas worlds which host large manufactorums drafted every soul capable of work to push out as many munitions and weaponry as they could to aid themselves and others.

Though even with these mighty efforts of self-preservation, being on the dark side of the rift has taken away something deemed essential for the Imperium to function: the Astronomican. A beacon on Terra, shining bright in the warp, this allows psykers to navigate void ships through the warp safely and send messages to other planets with relative ease and consistency. With the Astronomican being blocked from view by the Great Rift, space travel has slowed down to a crawl and messages are lost in transit, turn up too late, or worse – cause those who receive them to go mad with terrible nightmares.

To add to their woes, the forces of Chaos and other Xenos factions are largely unaffected by the lack of the Astronomican. Meaning that they are free to harass and attack these desperate worlds at their leisure. This being said, Imperial worlds, Space Marine Chapter planets, and other such bastions of mankind keep their torches lit and fight to maintain their worlds as strong as ever before.

What is technology like in Warhammer 40,000?

The way technology works in 40K is one of the things that really makes it stand out as a science fiction universe. This is especially true in the case of the Imperium, but it holds true for all factions.

The Imperium

The Imperium – or humans, to be more precise – in the 40K universe have a really bad track record with technological innovation. Many millenia before the 41st, there was a time called the Dark Age of Technology, where innovations in robotics and AI really propelled humanity forward, only for robots called the Men of Iron to rebel against humanity and wage war upon them. This led to a humanity-wide ban on artificial intelligence, and later, when the Imperium became the theocracy it ended up as, a general ban on the invention of new technology. As the years went by, knowledge dwindled and superstition increased, and in the “present” of 40K, the Imperium’s relationship with technology is more magical and religious than it is scientific. Most machines and weapons are reproductions of relics passed on from earlier eras of humanity, and often, knowledge about how they work has been replaced by ritual, so that tech-priests will anoint and bless tanks and guns to keep them working, just as much they will actually maintain and repair them. Machines are believed to be possessed by machine-spirits (which in-universe seems to be at least somewhat true and not just a superstition) with tempers of their own, and the only proper replacement for artificially intelligent computers are servitors, which are lobotomized human cyborg embedded within machines to give them some computing capacity. It’s backwards and horrifying, but in the Imperium, technology is in many ways a relic of the past, and something that is slowly fading.

This has changed a bit in recent years: The Adeptus Mechanicus and the Primarch Roboute Guilliman has infused the Space Marine legions with lots of new technology – most notably the improved Primaris Space Marines and their wargear, but for most of the Imperium, technology is still mysterious and clouded in awe and superstition.

While technically forbidden, some members of the Adeptus Mechanicus (particularly Belisarius Cawl) have been known to adapt and tinker with xenos technology in order to create equipment and machines to help mankind combat new and imposing threats. But this however, is highly dangerous due to accusations of tech-heresy and is often only attempted by members of the highest ranks.


The humans who worship Chaos generally have access to the same technology as the Imperium had at the time they rebelled against it, with the notable exception that their technology is warped, distorted – and sometimes improved – by the powers of Chaos. This means the Death Guard might have flamethrowers that can spew flames tainted by supernatural plagues, or a Chaos Space Marine of the Black Legion might wield a cursed sword. This mixture of technology and Chaos can especially be seen within the Dark Mechanicum – the tech-priests of Mars who rebelled against their brethren at the same time as the Space Marines did. These mad scientists and engineers blend bodies, machines and the energies of the warp without any of the restrictions of the Imperium, resulting in unspeakable, inhuman abominations who spread terror across the galaxy.


Like with everything else, Xenos technology is very diverse, but none of the other societies have quite as strained a relationship to it as the Imperium – which essentially means that new technology is available to the Imperium in all directions! Humans just aren’t interested in it due to religious taboos and the fear of a new Dark Age of Technology. The Aeldari mostly use ancient machines and weapons like the humans, but “ancient” to the Aeldari is still ages ahead of human technology. The Orks use whatever they can find (especially stuff with “lots ‘o dakka!”- many automatic shots from a gun or cannon), and the Leagues use what their Votann have passed on to them. The T’au and the Necrons are both advanced in their own way – the T’au are great at stealth and the use of artificially intelligent drones (they didn’t have any robot uprisings in their past), and the Necrons are themselves a great technological marvel, even to the point of possessing machines that can create parallel pocket dimensions and slow the passage of time in a limited area. Finally, the Tyranids aren’t really technological at all, as they’re purely biological, but their ability to direct their evolution allow them to surpass the more technological civilisations in many ways.

What is magic like in Warhammer 40,000?

“Magic” abounds in Warhammer 40,000, but it sort of has a scientific explanation in the way the Warp interacts with realspace. In this section, we look at what psychic powers are, and how they affect the wars of the 41st millenium.

The Warp

As described above, the Warp is a parallel dimension of energy that bleeds into “realspace” in many ways. Its most important function in 40K is that the Imperium and some other factions use the Warp as a shortcut across the galaxy for faster than light travel. It is a dangerous shortcut, however, as travelers in the warp subject themselves to psychic assaults by the powers that dwell in the Warp (think Event Horizon), and you’re never quite sure if you arrive at the right destination, or even at the right time! Imperial fleets have been known to arrive even centuries too late at a destination. To make warp travel work, Imperial ships use mutant Navigators (think Frank Herbert’s Dune universe) who can track the currents of the warp, as well as the Astronomican, a great psychic beacon projected into the warp by the Emperor from Terra.


Among the citizens of the Imperium, an ever-growing number of individuals are born as psykers, humans with psychic potential and a special connection to the warp. These are usually seen as threats and eliminated by the Inquisition or the Sisters of Silence (after all, you never know when one of them will suddenly manifest a gate to the Warp in the middle of a busy street), but some are trained to use their powers for the Imperium, and every day, scores of them are sacrificed to keep the Emperor’s work on the Astronomican in a working condition. Other civilisations also have psykers: some Aeldari Farseers can predict the future, the Grimnyr of the Leagues of Votann wield the power of their Votannic ancestors through a selective cloning of genes with psychic potential, but noone are more tapped into the psychic potential of the Warp than the Forces of Chaos.

Ruinous Powers

The Ruinous Powers, also known as the Chaos Gods, are god-like entities who inhabit the Warp. We’ve already described them above, so this section is dedicated to how they manifest in realspace. Apart from Chaos-worshipping psykers, of which there are many, the psychic powers of the Chaos Gods are most evident in the manifestation of Daemons, horrifying beings of pure Chaos energy who can step into realspace in physical form. Some are mindless horrors such as Bloodletters or Beasts of Nurgle, but some are magnificent powers in their own right, such as the mighty Daemon Princes. The apocalyptic scenario to end all apocalyptic scenarios in 40K is that the barrier between the Warp and realspace will be definitively destroyed, and that all reality will be consumed by such demonic entities.

What is war like in Warhammer 40,000?

The most important aspect of the Warhammer 40,000 universe, both in terms of its relevance to the games set within it and in terms of what stories you can find in novels and sourcebooks for the franchise, is war. None of the main factions in the lore are defined by what they do during peacetime: The Imperium is constantly defending and expanding itself; The Aeldari are fighting for their survival as a species; The Orks are fighting because it’s in their nature; The Necron are fighting to extinguish all life; The T’au are fighting for the greater good, and so on. Everyone is fighting, literally, for something, and against everyone else.

Ranged weapons and artillery, as well as all kinds of mechanized warfare, is common within most factions, and 40K has a couple of iconic weapon types such as the lasgun (sort of stolen from Dune) rifles that are basically the cheap AK47s of the 40K universe, and the terrifying bolters used by Space Marines, huge assault rifles that fire explosive rocket-like shells. Many factions, among them the Chaos Knights, Imperial Knights, Aeldari and T’au, use battlesuits or mechs that stride into battle as gigantic humanoids able to carry the heaviest guns and crush everything beneath their huge feet, and the Imperium are especially infamous for mass-producing World War 1-like tanks by the millions.

So far, so sci-fi, but alongside all these guns and vehicles, close combat weapons such as swords, hammers and axes are also present within almost every faction, giving warfare a medieval fantasy twist that’s a bit unusual in science fiction settings (again, a bit of Dune flavour here, but also Star Wars). Most famous among these melee weapons is undoubtedly the chainsword, a literal chainsaw on a sword hilt, which might be the single object that best embodies the over the top absurdity of 40K warfare. The use of melee weapons alongside ranged weapons give infantry combat in 40K an epic feel since it encourages duels and brawls that make for really fun action-packed storytelling, but they’re also part of what makes warfare in 40K grotesquely violent.

Warfare in 40K is also asymmetric: No two factions fight in the same way, and the scale of the armies that clash can vary greatly. Orks might attack in million-strong hordes, while the Imperial Adeptus Custodes who serve as the Emperor’s personal guard can hold off a small army with just a handful of their own soldiers. The Aeldari Harlequins fight battles as theatrical plays with artistry and flair, while the Adeptus Mechanicus fight their battles based on data and calculations, and the list goes on endlessly, with even subfactions within the same army having very different cultures of war.

Finally, warfare in 40K isn’t just fought on the ground. It is also fought between air forces within a planet’s atmosphere, and even between space ships in the void, maneuvering and firing broadsides like wooden ships of the line in the 1800s of our world.

Warhammer 40,000: Leviathan
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What are the most important events to know in Warhammer 40,000 Lore?

An important disclaimer is in order here: We’ve very deliberately kept this section ridiculously brief. If you’re in any way already into the 40K universe, you will no doubt pull your hair in frustration over everything that’s missing here: Where’s the Fall of Cadia? The Sabbat Crusades? The War for Armageddon? Here, however, we’ve chosen the two events that we believe are the most important events to know in order to understand what on Earth is going on in 40K at the moment.

The Horus Heresy

This one actually happens 10,000 years before the current timeline of 40K, but it defines almost everything about the universe, especially if you’re interested in Imperial or Chaos stories. You can read more about it in our Horus Heresy guide, but put very briefly, the story goes like this: After the Dark Age of Technology and the Age of Strife/Old Night, Terra was a wasteland of warring technobarbarians, warlords and despots. One day, a superhuman being who came to be called the Emperor of Mankind rose up and united the inhabitants of Terra, establishing the Imperium of Mankind. The Emperor then turned his attention to the stars, launching the Great Crusade to unite the scattered human-populated worlds and spread his Imperial Truth of secularism and rationality.

If you don’t think that sounds like the theocratic, despotic Imperium of Mankind you’ve been reading about in this article until now, you’re correct! The Imperium started out very differently to how it ended up, and the Emperor and his 20 Space Marine Primarchs originally set out to eradicate all religion and spread enlightenment. Unfortunately, something went really wrong with the Primarchs. Even as they were infants in cloning vats, they were whisked away by a mysterious event (something the Chaos Gods probably had a hand in) and were spread on different worlds across the Galaxy. As the Emperor’s Great Crusade progressed, the Primarchs were rediscovered and united with the Space Marine Legions at last, but they had all incorporated a lot of the culture of their involuntary homeworlds in their personalities and beliefs at that point.

In the beginning, this diversity was a good thing, and helped give the non-Terran part of the Imperium some cultural representation at its top. However, some of the Primarchs had acquainted themselves with the Forces of Chaos in different ways, often without realizing that’s what they were dealing with, since the Imperial Truth maintained that there were no gods in the first place. This was something the Chaos Gods were able to use to their advantage when the Emperor did something unexpected: On Ullanor, after the Crusade had defeated an Ork empire, the Emperor declared that he would return to Terra to work on a secret project for the good of all Mankind, while one of the Primarchs, Horus Lupercal of the Luna Wolves, were to be Warmaster in his stead.

Horus was a great warrior and a fearless leader, but he was also proud, and the Space Marines of the Word Bearers Legion, who had already turned to Chaos, were whispering half-truths in his ear disguised as friendly advice. When Horus was mortally wounded in a war to crush a rebellion, a local Chaos cult saved his life, and while he was struggling to recover in their temple, he was visited by the Chaos Gods in a vision. They showed him how the Emperor planned to defeat the Chaos Gods, twisting the story to mean that the Emperor was taking all the glory for himself and leaving his Primarch sons out in the cold, and as Horus emerged from the temple to the cheers of his legion brothers, a plan to betray his Father was growing within him.

Soon, Horus managed to sway some of the other Primarchs to his cause, and during a series of battles in the Isstvan system, he and his allies massacred a huge part of the Space Marines forces still loyal to the Emperor, as Horus openly declared his rebellion. As the great Imperial civil war raged on, the Traitor Primarchs and their legions grew ever more corrupted by the Forces of Chaos, and when the battle for Terra finally began, it was a horrifying siege of daemons and dark magic as well as bolters and chainswords.

Long war story short: In the end, the Emperor slew Horus, but he was also mortally wounded himself, and the Traitor Primarchs retreated into the Warp, while the Loyalist Primarchs were left to gather the pieces of a fractured Imperium. The Emperor was put on a kind of supernatural life support, his body decaying but his psychic powers seemingly intact, and the Imperium would never be the same for one additional reason: As the Heresy had unfolded, the one thing the Emperor had fought against had slowly become a core belief of many of his citizens. They believed that the Emperor was himself a God, as they had seen him intervene against the Forces of Chaos with great miracles throughout the war, and the administration of the Imperium took advantage of this in the wake of the Emperor’s near-death to slowly turn the Imperium into a bureacracy, forcing any idea of enlightenment and progress into hibernation for ten thousand years.

The Return of Roboute Guilliman and the Indomitus Crusade

Fast forward ten thousand years: The Imperium seemed almost certainly doomed when Ezekyle Abaddon, the Despoiler of the Black Legion and the leader of the human forces of Chaos, launched another of his Black Crusades, this time against Cadia, the one world that kept the gate to the Realm of Chaos closed. But then, one of the Loyalist Primarchs returned. They had all been gone for most of the last 10,000 years, either confirmed dead or just lost during the tumultuous years of the Heresy, but with the help of some notable Aeldari with an agenda of their own, and a genius Tech-Priest called Bellisarius Cawl, the Ultramarines Primarch Roboute Guilliman, was revived from the stasis he had been in for millenia.

Guilliman, a brilliant strategist and organiser as well as a formidable warrior, revitalised the fight for the survival of the Imperium – but he also brought unrest and worry to the bureaucrats of Terra because of his attitude towards them: Having been gone for the last 10,000 years, he was still a secularist at heart just like his Father had been, and he looked at the superstition and senility of Imperial theocracy with horror, hoping to once again let reason and enlightenment rule, even if it meant going against what was perceived to be the will of the Emperor. The Tech-Priest Cawl provided him with the means to put his ideas into action: Cawl turned out to have been working on a major upgrade for the Space Marine formula for millenia, revealing to Guilliman an army of supercharged Primaris Space Marines and the means to turn the original Space Marines, Guilliman included, into Primaris specimen as well.

With this newfound strength, Guilliman took the fight to the Black Legion, but not in time to prevent the destruction of Cadia. When Cadia fell, it caused a great rupture in realspace, called the Cicatrix Maledictum, opening a rift into the Warp that tore the galaxy in two. Worlds on the wrong side of the rift were cut off from the psychic beacon of Terra, and for more than a century, there was no contact between the Terran side and what was to be called the Imperium Nihilus, a place of horrors and Chaos incursions were only the most stalwart Imperial worlds held their ground.

Guilliman and his Primaris Space Marines then launched an expedition, the likes of which hadn’t been seen since the Great Crusade: The Indomitus Crusade collected the full might of the Imperium to reconquer what was lost – they were in many ways succesful, but the Black Legion turned out to be just one of the obstacles they would face: The Necrons had also awoken to stop the spread of Chaos, but unfortunately their (technically sound) plan for achieving this was to destroy all life in the galaxy, and as many other Xenos empires also took advantage of the situation, it sure didn’t seem like the Imperium was saved just yet…

What’s happening in the Warhammer 40,000 storyline right now?

In this section, we briefly track the latest storylines of Warhammer 40,000, so you have an idea of what’s currently going on.

The Arks of Omen

Most recently, Abaddon the Despoiler of the Black Legion has gained a new ally in Vashtorr the Arkifane, a mysterious daemonic being that seems to be the Chaos avatar of all things innovation and technology, and who is searching for an even more mysterious great weapon that will turn the tide of war. To aid their quest, they have summoned a great fleet of space hulks, deserted floating scrap yards of Warp-capsized space ships, into real space, and Vashtorr started enhancing them and turning them into great weapons of war. They are called the Arks of Omen (the title of the storyline), and they were sent out across the Galaxy to find all the pieces of a key that Vashtorr needs to unlock a great weapon that he plans to use to destroy the Imperium.

As they ventured forth, they had to fight the Imperium and xenos factions to claim their prizes. During this time Angron, the Daemon Primarch of the World Eaters returned to destroy a world that just so happened to be a target for Vashtorr and his Arks of Omen. During this battle and many more like it, Vashtorr would find all the pieces he would need to unlock this powerful artifact, now he only needs to find the lock in which this great weapon is held behind. Though he succeeded, many Imperial heroes such as Dante of the Blood Angels and Azrael of the Dark Angels would team up with Lion El’Johnson: the Primarch of the Dark Angels, who had only recently been reawakened to protect his battle brothers from the onslaught of Vashtorr, Abaddon and Angron.

The Seventh Way

The Ynarri (a religious sect of Eldar from all walks of life) believed that they could save their species from having their souls under threat of the Chaos God Slaanesh. Yvraine, a prophet and the leader of the Ynarri, sought out to awaken the Eldar Aeldari god of the dead: Ynnead by collecting 5 legendary Croneswords. In theory, this could have defeated Slaanesh once and for all. Or at the very least, kept her at bay and allowed the Aeldari to no longer live in fear.

They have been active in the galaxy to achieve this goal, even playing a part in the resurrection of Roboute Guilliman, but unfortunately, the fifth Cronesword was to be located within the Palace of Slaanesh herself; making the task all but impossible to accomplish. Rather than lose hope in despair, Yvraine now seeks another way to defeat Slaanesh.

The Great WAAGH!

Ghazghkull Mag Uruk Thraka has long been the biggest and meanest Ork Warboss to threaten the Imperium. As a prophet of the Great WAAGH! Ghazghkull is constantly growing his horde of Ork Boyz. For a long time his attention was focused around Armageddon, a planet that provided everything an Ork Warboss could ever want: a good scrap. He had a long time rival, Commisar Yarrick, to fight against. With Yarrick missing in action however, the Great Prophet has moved onto other worlds in the galaxy to continue fighting, and growing in strength.

The Silent King Returns

The last of the Necron Silent Kings, Szarekh, spent uncountable years in self-exile after he unwittingly transformed his entire race into soulless metallic creatures. His goal was to find other organic species in which he could find suitable bodies for those Necron minds who still function, but with Chaos and Tyranids threatening the galaxy, he has returned to unite the Necron dynasties in the hopes to push back these threats.

The Third Tyrannic War

A species defined by its ability to adapt, the Tyranids have began an intense assault on the southern border of the Segmentum Solar – the region of space in which Holy Terra is located. Roboute Guilliman is currently leading the charge in defending the Imperium’s home sector from the approaching xenos threat, but things are looking bleak.

Where can I learn more about Warhammer 40k Lore?

If you’ve read through this article and come away with a desire to know more about the Warhammer 40,000 universe, or perhaps even get involved with the gaming side of things, there are many ways you can go, and here are just a couple of them:

  • Black Library Books: Games Workshop has a publishing label that does nothing but release stories about Warhammer, the majority of them being about the Warhammer 40,000 universe. The quality of the writing and storytelling in these books vary a lot, but many of them are great fun, and some are even good science fiction books in their own right. You can read our beginner’s guide to 40K Black Library books here. A good tip is to listen to them as audiobooks: No one does audio books quite like Black Library, as they’re often narrated by fantastic voice actors, and listening through something like the Horus Heresy series (more than 40 books!) while you work, cook, clean or exercise can quickly start feeling like watching a really good Netflix show.
  • Warhammer TV: Games Workshop has its own streaming platform, which does a lot of hobby stuff, but also some really great lore videos and an ever-growing library of animated shows from the worlds of Warhammer. If you get a Warhammer+ subscription , you get Warhammer TV and the Warhammer Vault, which is also full of cool digital sourcebooks.
  • Fan wikis and video content: Like all good fandoms, the 40K fandom has done a great job at cataloguing 40K lore in fan-made wikis where you can look up anything without having to read three novels about Space Marines killing things with chainswords first. Lexicanum is one of the good ones. On Youtube, you can also find a lot of great (and really, really, really unapologetically nerdy) 40K lore content. The quality varies a lot, and some of it is a bit tonally off-putting (not everyone in the 40K fandom agrees that 40K is satirical in its depiction of fascistoid macho warrior culture), but someone like Arbitor Ian does a great job of making 40K lore accessible for beginners and longtime fans alike.
  • The games (!): Of course, there’s no better way of getting into 40K lore than to start playing 40k games. You can read our guides to the Warhammer 40,000 tabletop wargame, the tactical skirmish game Warhammer 40,000: Kill Team (which we really, really love here on Age of Miniatures), the narrative-focused almost-roleplaying game skirmish game Necromunda and the great 40K-historical wargame Warhammer: The Horus Heresy here on the site. We love 40K games, and we’re constantly expanding our coverage of them. There are also a couple of great 40K pc games out there, most notably Warhammer 40,000: Darktide, and a ton of pretty bad ones that you can still enjoy just for the 40K flavour.

Other great resources:

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