Warhammer 40,000 is more than just a tabletop wargame with miniatures and dice; it’s a vast, immersive fictional universe cultivated by Games Workshop for four decades. Every month brings new additions to the Warhammer 40,000 story through books and model releases. Online wikis and YouTube channels contribute daily to the ever-expanding body of Warhammer 40k lore. This constant influx can overwhelm newcomers. This comprehensive guide provides beginners with essential information to navigate the grim darkness of the far future. We’ll cover fundamental concepts, key factions, their histories, and the current state of the storyline. While we can’t cover everything, this primer will encourage you to explore the 40k universe, whether you’re planning to play the game, read the novels, or simply expand your knowledge of science fiction franchises.
What Genre is Warhammer 40,000?
The simplest answer is science fiction, which is accurate in many respects. Like most sci-fi worlds, Warhammer 40k takes place in the future – the very distant future. It also uses advanced technology that hasn’t been invented yet, exploring the moral and political consequences of its use.
However, 40k isn’t typical space-faring science fiction like Star Trek.
First, it’s deeply pessimistic and dystopian. Nearly everything has gone wrong in the future of the 40k universe. Progress and enlightenment are scarce, with few exceptions in certain factions and recent plot developments.
Second, technology has devolved in many ways. If you disregard the spaceships and lasers, 40k could easily be a dark fantasy epic with ancient heroes battling monsters, wielding legendary swords and magical powers.
What draws 40k closer to fantasy is the presence of races akin to those in The Lord of the Rings. Heroic humans exist, but so do high elves (the Asuryani Aeldari), dark elves (the Drukhari), orcs (the Orks), ogres (Ogryn), hobbits (Ratlings), dwarves (The Leagues of Votann), and even undead (Necrons).
These races differ significantly from their medieval fantasy counterparts. The Aeldari are still ancient and dwindling, but they travel on spaceships filled with the souls of the dead. The Votann remain smiths and artisans, but they’re also clones. The Orks don’t serve a dark overlord; instead, they spread joyous violence across the stars. The Necrons are undying, unfeeling entities dwelling in living metal that self-reconstructs upon destruction, rather than crumbling undead bodies.
While 40k incorporates major science fiction and fantasy elements, its individual stories span a diverse range of genres. There are film noir-esque crime stories set in megacities, farcical comedies about Orks, classic pulp adventures for young readers, gritty war stories of infantry squads in muddy trenches, and numerous horror stories.
The shorthand term for 40k’s unique genre blend is “grimdark.” This term perfectly captures the sheer hopelessness and terror that pervades the 40k universe, depicting a future that has turned out in the worst possible way.
When and Where Does Warhammer 40,000 Take Place?
Warhammer 40k primarily takes place roughly 40,000 years in the future, during the 41st millennium AD. There’s a detailed backstory set 10,000 years prior, and recently, the storyline has begun to move slightly into the 42nd millennium. However, for most of its history, the setting has remained anchored around the 40,000 AD mark.
The setting is our galaxy, featuring familiar locations like Earth (called Terra) and the Sun. However, the galaxy is largely unrecognizable. Humanity has colonized much of it, but various alien species also control significant territories. The galaxy is also closely connected to the Immaterium, or the Warp, a horrifying parallel dimension. This Chaos-infested realm defies physics, but civilizations use it as a dangerous and unreliable shortcut for interstellar travel.
Currently, the galaxy is split by a massive rift that leads into the Warp, dividing it into two halves. Terra and our solar system are on one side, while the Imperium Nihilus, a human-controlled region with unstable contact with Terra, is on the other.
What are the Most Important Factions in Warhammer 40k Lore?
The Imperium of Mankind
The Imperium of Mankind is home to countless billions of humans across the galaxy. Over 10,000 years old, the Imperium is perpetually on the verge of extinction due to numerous internal and external threats. The official leader is the God-Emperor of Mankind – an immortal, psychic warrior and genius who united humanity. Today he is an artificially sustained corpse protecting the Empire from Chaos with his psychic powers.
In reality, the Imperium is governed by a monstrous bureaucracy of administrators, generals, and priests, functioning as a theocratic police state. Religious doctrine and paperwork maintain a semblance of control.
To defend itself, the Imperium relies on various military and paramilitary organizations, notably the Space Marines and the Astra Militarum.
The Space Marines are superhuman elite warriors, genetically altered and biomechanically augmented. Originally, the Emperor created twenty Legions of Space Marines each with their own Primarch leaders. The Space Marines are physically superior to regular humans.
They’re taller and stronger, with distorted features due to implants and extra organs (including two hearts). They’re also nearly immortal. Their separation from humanity stems from their warrior-monastic cultures. The Blood Angels suffer from a vampiric disease rooted in the death of their Primarch, driving them to berserk states. The Iron Hands replace limbs with mechanical augments. The Space Wolves crave glory but bear a curse that transforms them into wolf-like beasts. The Black Templars are xenophobic crusaders covered in religious iconography.
Despite their inhuman nature, the Space Marines are crucial to humanity’s survival, enabling the Imperium to compete with advanced alien species.
The Astra Militarum is the Imperium’s other main military force. Instead of superhuman augmentation, it relies on the vast resources of Imperium-controlled worlds. The Astra Militarum is essentially the human army, composed of billions of soldiers recruited from across the galaxy. Many planets have distinct military traditions. The Astra Militarum also employs mass-produced tanks and artillery. This makes it closely resemble a futuristic and exaggerated version of a World War I army.
Numerous other subfactions exist within the Imperium, including the Adepta Sororitas, the Mechanicum, the Ecclesiarchy, and the Inquisition.
The most important thing to know about the Imperium is that it is not the “good guy.” The Imperium is a cruel, oppressive civilization that treats its citizens and enemies horribly.
The Imperium’s leaders are often villains to other species and even to fans. Yet, they are the humans of the setting, making it natural to identify with them. This is part of what makes 40k so compelling: it forces identification with something reprehensible, prompting reflection on the ways in which the Imperium mirrors negative aspects of human behavior, albeit in an exaggerated and satirical way.
The Forces of Chaos
Some choose to reject the God-Emperor and embrace the Ruinous Powers, godlike entities in the Warp. These entities grant supernatural powers at a great price. The Forces of Chaos are enemies of the Imperium, the Aeldari, and many other civilizations.
The Chaos Space Marines are the remnants of Space Marine Legions who embraced Chaos. They followed their Primarchs in rebellion against the Emperor 10,000 years ago.
Like loyal Space Marines, they are superhuman warriors in power armor. But Chaos has twisted each Legion’s culture, making them even stranger. The Death Guard worship Nurgle, the Chaos God of Decay, and are covered in flies. The World Eaters worship Khorne, the Chaos God of Rage, and charge into battle with chainaxes. The Emperor’s Children worship Slaanesh, the Chaos God of Excess, and use alien organs to kill with screams. The Thousand Sons worship Tzeentch, the Chaos God of Magic and Change, and are dust golems and arcane sorcerers.
Some Chaos Space Marine chapters, like the Night Lords, avoid worshipping the Chaos Gods and focus on their war against the Imperium.
Ezekyle Abaddon of the Black Legion leads these forces, vowing to destroy the Imperium.
Deserters from the Astra Militarum, known as the Traitor Guard, also fight for Chaos. Daemons of Chaos, manifestations of the Warp’s horrors, invade the galaxy.
The Xenos
“Xenos” is an Imperial term for anything not of human origin. The Xenos encompass diverse alien civilizations that compete with the Imperium. While the 40k game features a limited number of Xenos factions, the lore includes dozens, ranging from isolated monsters to vast civilizations. The most important ones are:
- The Aeldari: Once ruled the Galaxy, but their quest for perfection led to hedonism and the creation of Slaanesh, who consumes Aeldari souls. Their race is dwindling and scattered. The Asuryani Aeldari strive for righteousness through self-control, saving souls from Slaanesh. The Drukhari revel in pain and suffering as feared raiders and torturers. The Ynnari seek to unite all Aeldari to create a new god of Death. Like Tolkien’s elves, Aeldari are ancient and graceful, but arrogant and dismissive of short-lived humans. They are often enemies of the Imperium but cooperate when foresight reveals a path to a better future.
- The Orks: The green menace of the galaxy and archenemies of the Imperium for over 10,000 years. They are a war-focused society of hulking brutes who grow stronger the more they fight. They seem to grow like fungus and rapidly multiply whenever they launch Waaaghs! More than anything, the Orks find joy in fighting, making them a positive faction.
- The Necrons: A mechanical civilization of intelligent automatons. Once flesh and blood, they transferred their minds into metal bodies eons ago to win a great war. Recently, they have risen to rid the galaxy of biological life and silence the Warp. Their advanced technology makes them almost immortal, and their leaders resurrect them from even severe damage. Wherever they go, life ends.
- The T’au: The T’au rule a relatively small, advanced, peaceful, and prosperous empire at the fringes of the Galaxy. They serve the Greater Good, guided by their leaders. They are a skeptical, progressive, and tolerant society, incorporating other species into their empire. Some humans even prefer joining the T’au to living under the Imperium. However, they are also formidable warriors.
- The Tyranids: The most inhuman Xenos. They are a locust swarm of biological horrors, consuming and integrating all biological matter to serve Hiveminds. They infiltrate worlds with Genestealers, who incite revolutions and worship Tyranids as saviors. When the rebellion nears victory, the Tyranids arrive to devour everything, including the cults.
- 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?
Warhammer 40k’s stories delve into the structure of societies within the universe, particularly the Imperium of Man.
Faith and Heresy
Everyday life in the Imperium is permeated by religion. Devotion to the Emperor is mandatory, and religious rituals are integral to all aspects of life. The worship of the Emperor influences architecture and design, resulting in structures adorned with spires, mosaics, and angelic sculptures. This aesthetic is often described as “Space Catholic.”
Deviation from religious dogma is not tolerated. Heresy is a major taboo, policed by the Inquisition, law enforcement, and even the Space Marines. Since the Horus Heresy, rejecting the Emperor has been deemed a primary threat, consuming vast resources to contain.
Diversity and Bureaucracy
Humanity’s 20,000-year presence outside Terra has led to diverse cultures across the Imperium’s worlds, shaped by different climates and historical developments. Some worlds are medieval, with knightly orders protecting farmers from monsters. Hive cities house billions in squalor, manning industrial complexes for the war machine. Shrine worlds attract galaxy-spanning pilgrimages. The Imperium maintains order through Emperor worship, taxation, and military aid. A massive bureaucracy manages this, collecting tithes and information to coordinate war efforts.
The Astra Militarum exemplifies the Imperium’s diversity, with regiments from various cultures. The Cadians, hardened by defending against Chaos incursions, are a revered fighting force. The Death Korps of Krieg, siege specialists in gas masks, atone for past transgressions with disregard for their safety. The Catachan are fierce jungle fighters.
Mutation and Xenophobia
“Abhor the mutant” and “Suffer not the alien to live” are common Imperial mottos. Mutation is common due to human evolution and exposure across the Galaxy. The Imperium tolerates some mutations, such as the Ogryn, but purity of the human species is vital. Mutants deviating too far from the baseline are exterminated.
The Imperium also strictly enforces the boundary between human and alien. Relations with Xenos are strained; in most cases, humans kill aliens on sight. There are exceptions, such as temporary alliances with the Aeldari. Rogue Traders can cooperate and trade with aliens if it benefits the Imperium.
Other Societies
Many human worlds are ruled by Chaos, and Xenos societies are diverse. Like the non-human races of The Lord of the Rings, they are defined by their differences from humans. The Aeldari are ancient and superior, while the Orks are playfully insane and strong. Some Xenos societies are more fleshed out in the lore than others.
Imperium Nihilus
The Imperium is already a rough place for most, but it has been made much worse since the Cicatrix Maledictum rent the galaxy in two. The worlds on the Terra side of things remain largely unchanged. On the other side of the rift 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?
Technology in 40k is a distinguishing feature, especially within the Imperium.
The Imperium
The Imperium has a poor record of technological innovation. The Dark Age of Technology saw advances in robotics and AI, but robots called the Men of Iron rebelled, leading to a ban on AI and later, a general ban on invention. Knowledge dwindled, superstition increased, and the Imperium’s relationship with technology became magical and religious. Machines and weapons are relics from earlier eras, with ritual replacing knowledge. Tech-priests anoint and bless tanks and guns, believing in machine-spirits. Artificially intelligent computers are replaced by servitors, lobotomized human cyborgs embedded in machines.
This has changed recently. The Adeptus Mechanicus and Roboute Guilliman have introduced new technology, like the Primaris Space Marines. However, technology remains mysterious and clouded in awe and superstition for most of the Imperium.
While technically forbidden, some members of the Adeptus Mechanicus 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.
Chaos
Chaos worshippers have access to technology warped or enhanced by Chaos. The Death Guard may have flamethrowers spewing supernatural plagues, while a Black Legion Chaos Space Marine might wield a cursed sword. The Dark Mechanicum, tech-priests who rebelled with the Space Marines, blend bodies, machines, and Warp energies without restrictions, creating inhuman abominations.
Xenos
Xenos technology is diverse. The Aeldari use ancient machines, which are still advanced compared to human technology. The Orks use anything they can find, especially weapons with “lots ‘o dakka.” The Leagues use technology passed down by their Votann. The T’au excel in stealth and drones, while the Necrons possess machines that can create parallel dimensions and slow time. The Tyranids are purely biological but can surpass technological civilizations through directed evolution.
What is Magic Like in Warhammer 40,000?
“Magic” in Warhammer 40,000 has a scientific basis in the Warp’s interaction with realspace.
The Warp
The Warp is a parallel dimension that bleeds into realspace. It is used for faster-than-light travel, but is dangerous, subjecting travelers to psychic assaults and uncertain destinations. Imperial ships use mutant Navigators and the Astronomican, a psychic beacon projected by the Emperor.
Psykers
An increasing number of individuals are born as psykers, humans with psychic potential. They are usually seen as threats and eliminated, but some are trained to use their powers for the Imperium. Other civilizations also have psykers. Noone are more tapped into the psychic potential of the Warp than the Forces of Chaos.
Ruinous Powers
The Ruinous Powers, or Chaos Gods, inhabit the Warp. Apart from Chaos-worshipping psykers, their psychic powers manifest in Daemons, beings of pure Chaos energy who enter realspace. Some are mindless horrors, while others are powerful Daemon Princes. The apocalyptic scenario in 40k is the destruction of the barrier between the Warp and realspace, consuming reality with demonic entities.
What is War Like in Warhammer 40,000?
War is central to the Warhammer 40,000 universe. All factions are defined by their engagement in constant conflict.
Ranged weapons, artillery, and mechanized warfare are common. Iconic weapons include lasguns and bolters. Many factions use battlesuits or mechs, and the Imperium mass-produces World War 1-like tanks.
Close combat weapons are also present, adding a medieval fantasy twist. The chainsword, a chainsaw on a sword hilt, embodies the over-the-top absurdity of 40k warfare. Melee weapons give infantry combat an epic feel, encouraging duels and brawls, but also make warfare grotesquely violent.
Warfare in 40k is asymmetric. No two factions fight alike, and the scale of armies varies. Orks attack in million-strong hordes, while the Adeptus Custodes can hold off small armies with just a handful of soldiers.
Warfare is fought on the ground, in the atmosphere, and in space.
What are the Most Important Events to Know in Warhammer 40,000 Lore?
This section is deliberately brief, focusing on the two most important events for understanding the current state of 40k.
The Horus Heresy
This event happens 10,000 years before the current timeline and defines much of the universe, especially Imperial and Chaos stories. After the Dark Age of Technology and the Age of Strife, the Emperor of Mankind united Terra and launched the Great Crusade to unite scattered human worlds.
The Imperium started out differently, with the Emperor and his 20 Space Marine Primarchs seeking to eradicate religion and spread enlightenment. However, something went wrong with the Primarchs. As infants, they were whisked away by a mysterious event and scattered across the Galaxy. As the Crusade progressed, the Primarchs were rediscovered, but they had incorporated the cultures of their homeworlds.
This diversity was initially beneficial, but some Primarchs encountered the Forces of Chaos, often unknowingly. The Emperor declared he would return to Terra for a secret project, appointing Horus Lupercal as Warmaster.
Horus, a proud leader, was swayed by the Word Bearers Legion, who had already turned to Chaos. Wounded in battle, a Chaos cult saved his life, and the Chaos Gods showed him a vision of the Emperor taking all the glory for himself. Horus then plotted to betray his Father.
Horus swayed other Primarchs to his cause and massacred loyal Space Marines. The civil war raged, and the Traitor Primarchs grew corrupted by Chaos. The battle for Terra was a siege of daemons and dark magic.
The Emperor slew Horus but was mortally wounded, and the Traitor Primarchs retreated into the Warp. The Emperor was put on life support, and the Imperium changed. The Emperor became seen as a God, and the administration turned the Imperium into a theocracy, suppressing enlightenment and progress.
The Return of Roboute Guilliman and the Indomitus Crusade
Ten thousand years later, the Imperium seemed doomed when Abaddon launched another Black Crusade against Cadia. But then, Roboute Guilliman was revived.
Guilliman revitalized the fight for the Imperium’s survival but worried the Terra bureaucrats with his secularist views. Tech-Priest Cawl provided him with upgraded Primaris Space Marines and the means to transform the original Space Marines, Guilliman included, into Primaris specimen as well.
With this strength, Guilliman fought the Black Legion, but not in time to prevent Cadia’s destruction. Cadia’s fall caused the Cicatrix Maledictum, tearing the galaxy in two. Worlds on the wrong side were cut off from Terra.
Guilliman launched the Indomitus Crusade to reconquer lost territory. The Black Legion, Necrons, and other Xenos empires opposed him.
What’s Happening in the Warhammer 40,000 Storyline Right Now?
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’re eager to delve deeper into the Warhammer 40,000 universe, or even explore the gaming aspect, numerous avenues are available.
