The Lore Explainer: The Ultramarines, Part 2 - The XIII Legion

In our Lore Explainer series we take a deep look at the lore of various games, settings, and factions. In this article we're looking at the lore behind the Ultramarines, the XIII legion of space marines and the ostensible poster boys of the Warhammer 40,000 universe. Specifically, we're looking at their history during the Horus Heresy.

Welcome back to our five-part series on the lore of the Ultramarines. Last time around we talked about the basic lore of the Ultramarines, from their general deal and chapter organization to their major conflicts. If you missed that article, you can find it here. This time around we'll be talking about the Chapter's history in the Horus Heresy, from their founding as the the Thirteenth Legion to the Unremembered Empire and their role in the final days of the Heresy.

Before we dive in, it's worth remembering that the legions of the First Founding were created separate from their Primarchs. When the Primarchs were still infants in their birthing tubes they were cast through the warp by the Chaos Gods and scattered across the galaxy. Before the launch of the Great Crusade, the Emperor would create the first legions from the gene seed of those Primarchs and recruits on Terra. So when the Crusade finally began, the Emperor marched out at the head of vast Space Marine Legions.

The XIII Legion, the War-born

The first Ultramarines were recruited from the Midafrik Hive Oligarchy, the war families of the Sargon Enclave, the sub-equatorial maglev clans of Panpocro, and the martially-skilled tribes roaming the Caucasus Wastes (despite them being a bunch of cannibals). These people had all fought longer than most into the Unification Wars, resisting assimilation to the last days of the campaign, almost to their own extinction. These tenacious, determined, selfless fighters would become the first Ultramarines, and they were initially known as the War-born. When these traits were combined with Guilliman's gene-seed they became calmer and more goal-oriented, with a marked increase in cohesion and hierarchy building.

The War-born were initially responsible for fighting in early campaigns off Terra, including the Pacification of Luna and the Sedna Campaign. The capture of the Selenar Gene-Cults' Lunar laboratories would enable the mass production of space marines and following the campaign the numbers of the War-born grew quickly, in part due to the stability and robustness of their Primarch's gene-seed. The Thirteenth Legion quickly became known as a practical and forthright Legion; loyal, proud, and professional under the leadership of Lord Commander Gren Vosotho.

The Osiris Cluster Rebellion

The XIII Legion had much success in the Great Crusade, oftentimes fighting alongside other Legions. It was in these battles, such as the purgation of the Cancerai Nebula and the crushing of the Orks at Cypria Mundi, that cemented the XIII's reputation. But such success would not last.

Early into the Great Crusade, the XIII Legion were responsible for the rediscovery and conquest of the planets in the Osiris Cluster, a group of eleven star systems in Segmentum Solar. This highly successful campaign swiftly brought the technologically advanced worlds of the system into compliance with minimal bloodshed and it was a bright mark on the record of the XIII legion.

Then thirty years later, the Osiris Systems erupted into rebellion, declaring independence from the Imperium. Deciding to "look into" the matter and "just wanting to talk to them," Lord Commander Gren Vosotho, led an expeditionary force into the Cluster, where they were promptly ambushed by a Xenos fleet. This race of incorporeal psychic beings in baroque armor would come to be known as the Osirian Psybrids and they'd promptly kick the XIIIth's Legion's collective asses, killing more than 6,500 marines, Lord commander Vosotho, and destroying a quarter of their expeditionary fleet. Even the Legion's flagship, the Sethaln's Thunder, was destroyed by the Psybirds. By the time the legion returned a year later with reinforcements from the XVIII and the Solar Armada, they found only barren wastelands and no sign of the Xenos invaders.

Meanwhile, on Macragge...

While the War-born were embarked on the Great Crusade their Primarch, Roboute Guilliman, was growingly quickly on his adopted home world of Macragge. By the time the Emperor of Mankind reached the Macragge system he had already heard rumors of the prodigal son of Consul Konor, and was pretty sure said boy was one of his lost Primarchs. When the Emperor arrived he found Macragge to be a prosperous and shining example of mankind's best traits. The recruited Guilliman was placed in charge of the XIII legion, who were renamed the Ultramarines and relocated to Macragge as their new homeworld.

From there Guilliman's empire grew and only the Luna Wolves conquered as many worlds as the Ultramarines. The Ultramarines didn't simply raze or liberate worlds; they'd establish new Imperial strongholds, leaving prosperous, efficient, self-sufficient worlds in their wake. They'd establish trade routes and leave behind advisors and industry. These prosperous worlds would then feed back into Guilliman's empire and his legion, further fueling their growth and power. Meanwhile, Guilliman's restraint and tactical genius would often see fewer casualties per battle in his conquests. They avoided long wars of attrition that might drain their numbers, leaving them with the largest of the Space Marine legions.

On a fun note: Black Book 5 makes it clear that the Emperor knew about Guilliman when the XIII legion were sent to investigate the Psybrids and just withheld that information from them. It wasn't the only time He would arrange for a legion to get its asses kicked right before "finding" their primarch - He pulls the same trick again with Vulkan and the Salamanders and the XVIIIth Legion.

Xenocide at Eurydice Terminal

It had been some time since the Ultramarines or anybody had heard from the Osirian Psybrids when a War Hounds (eventually World Eaters) fleet was attacked by them while engaged in battle with Ork raiders. When Guilliman found out, he ordered the War Hounds to track down the Psybrids' vessels, following them to the Eurydice Terminal. There the Ultramarines systematically wiped out the Psybrids, and with them their enslaved Human and Ork armies. The battle enacted a heavy toll on the Ultramarines and War Hounds, but Guilliman had finally enacted bloody vengeance for his legion sixty years after their humiliation.

That Time They Had to Teach Lorgar a Lesson

Of all of the Primarchs, Lorgar was by far the most pious, having been discovered on the Feudal World of Colchis and raised in a series of religious wars. Lorgar's legion worshipped the Emperor as a god, and as the Word Bearers conquered planets they'd build shrines and churches to the Emperor, burning ancient scrolls and art that might challenge the Emperor's divine authority. The Word Bearers did not just conquer - they converted worlds to the worship of the Imperial Faith.

But conversion was slow work, taking more time and resources as the Word Bearers would spend years bringing their teachings to a world. On top of that the Emperor was not a fan of Lorgar's worship nor the spread of his doctrine. And so as the Word Bearers' progress slowed to a crawl the Emperor decided to finally rebuke Lorgar and force him to re-pledge his legion to the Great Crusade. This all went down on Khur, a world brought into compliance by the Word Bearers, in its captial city of Monarchia.

The Word Bearers had built Monarchia to be a perfect city, a shining example of everything the legion stood for. Its citizens had an intense religious devotion to the Emperor as humanity's god and the place was lousy with cathedrals. The Emperor called Guillman and the Ultramarines to the city where they had the entire Word Bearers legion assemble on the planet's surface and watch as they evacuated the city's population, then razed it to the ground. Then the Emperor made every Word Bearer kneel, admit that they'd failed the Imperium, and re-pledge themselves to the Crusade, saying that He was no god and wasn't going to put up with any of that bullshit.

Guilliman wasn't particularly happy about being asked to publicly rebuke his brother and destroy the Word Bearers' shining city on the hill, but he did it anyway. As you might expect, this action drove a wedge between the two Legions. The Word Bearers came to resent the Ultramarines and Lorgar particularly hated Guilliman for his role in the razing of Monarchia.

Other Adventures of the XIII Legion

The Ultramarines, being a big empire-building Legion at the galactic frontier, had other notable adventures. On the world of Thoas, Roboute Guilliman led the Ultramarines against the Orks, with the 22nd Chapter (discussed below) taking a central role in the purgation of the planet. The planet was a human world that had been lost in Old Night, and Guilliman was eager to uncover it's history and records. Unfortunately, the fighting revealed that the main records and legacy left by this lost human civilization was an arsenal of weapons of mass destruction (atomic, biological, chemical, and various mixes and matches) and records clearly indicating that the inhabitants of Thoas had turned those weapons on themselves. Guilliman ordered the Destroyer companies of the Nemesis Chapter to secure the remaining weapons, then the Ultramarines fleet to wipe out the last remaining traces of the civilization. The Primarch stated: "I want an orbital bombardment of the ruins. Flatten them. This is an unprofitable history for future settlers. This was not a culture here. It was an irrational mistake. Its memory has no place in my Father's Imperium."

Guilliman was also keen to use diplomacy to entice worlds to join the Imperium and the 500 Worlds. One such world on the edge of his empire was Nuceria, a world with samples of advanced technology, lots of people, and while Guilliman was finishing up negotiations a gladitorial slave uprising. That's when The Emperor Himself arrived, to take custody of the leader of the slave rebellion and put him in charge of the XII Legion. Guilliman's attempts to bring Nuceria into the Imperium and the 500 Worlds would have, eventually, terrible consequences for everyone involved.

Ultramarines hold the line at the Siege of Marinus

The Organization of the XIII Legion

Even in the days of the War-born, the various sub-formations of the Ultramarines adopted a wide variety of names, logos, and doctrines for themselves. The 22nd Chapter, which was focused on units of Destroyers and infamously fought alongside the VIIIth Legion, named themselves the Nemesis. The 4th Chapter maintained principally amoured formations commemorated a tank battle against the Orks with the symbol of the aurora borealis of Cypria Mundi. By the time of reunification with the Primarch, this practice had become entrenched and would serve as one of the reasons Guilliman split the Legions into Chapters. By the start of the Horus Heresy, the Ultramarines counted at least twenty five Chapters in their ranks - some two hundred and fifty thousand Marines in their number.

The Horus Heresy - The Shadow Crusade

The Ultramarines may have missed the fighting at the Siege of Terra but were no less busy during the Heresy - they were the target of a brutal campaign intended to keep them from providing aid to the Emperor while enacting revenge for Monarchia. This campaign to fight the Ultramarines on the Eastern Fringe of the galaxy across the 500 worlds of Ultramar was called The Shadow Crusade.

For Horus, the Ultramarines were a problem. Guilliman's legion was the largest and most capable of the Space Marine Legions, and Horus himself considered Guilliman one of his closest advisors. Horus also knew the Ultramarines would never support his treachery and so before declaring his campaign he ordered the Ultramarines to galaxy's southern rim to fight back against an Ork invasion in the Veridian System. Specifically, on Calth - one of the 500 worlds of Ultramar and one of its most productive planets, renowned for its orbital shipyards and massive underground cities.

Count Begins: Calth Mark 00:00:00

Horus ordered the Ultramarines to deploy to Calth alongside a massive force of the Word Bearers - both legionary and mortal forces - in anticipation of the Ork invasion. Guilliman and his forces, ignorant of the betrayal at Isvaan, assembled to prepare for battle in the system unaware that they were walking into an ambush but generally feeling that something was off the moment they arrived. Specifically, they were cut off from the rest of the Imperium by Warp Storms, unable to get messages in or out.

There were other signs, of course - all the kinds of creepy nonsense you might expect from a traitor force turned to Chaos preparing a massive betrayal were there: Ominous chanting over the vox channels, lapsed psykers of the Ultramarines' legion coming down with headaches and nausea (since the Emperor had decreed psykers to be illegal at the Council of Nikea, the chapter's psykers had been redeployed to more standard roles), and scrapcode infesting their ships' systems. But most of these were dismissed as random distortion prior to what Guilliman believed to be a political exercise designed to show power and build good PR for the Word Bearers more so than a real campaign against a serious threat.

...and that's when the Word Bearers attacked. It started with Word Bearers forces seizing the fleet tender Campanile, accelerating it to 40% light speed, and sending it through Calth's orbital shipping belt and into its Shipyard. The subsequent explosions and collisions effectively created a Kessler effect that shattered Guilliman's precise and tightly-organized logistics throughout Calth's gravity well and generated a massive EMP shockwave. Major warships and troop transports were destroyed, communications severed, and power lost. Then the Word Bearers and their cultist forces attacked the dazed Ultramarines in earnest. Guilliman, believing this to be a tragic mistake, implored Lorgar to stop, only to be greeted by a gloating Lorgar via hologram, happy to inform him of Horus' treachery and the Dropsite Massacre before unleashing a daemon against them. Guilliman ordered his forces to defend themselves at all costs and return fire.

Know No Fear and the Underground War

At the commencement of the Mark of Calth, many of the legion's greatest heroes were aboard Guilliman's flagship, Macragge's Honour: Guilliman himself, Chapter Master Marius Gage, and censured Sergeant Aeonid Thiel were all standing by as Lorgar unleashed daemons upon the warship. Meanwhile on the planet's surface, Tetrarch Remus Ventanus rallied the scattered forces of the Ultramarines, Auxillia, and Mechanicum in order to make a stand against the Word Bearers and retake control of the planetary defense network. The Ultramarines fought a number of desperate battles to regroup and survive the Word Bearers' devastating sneak attack and there were a number of very cool moments in this battle, such as the Contemptor Dreadnought Honoured Telemachus being blown off the warship, falling to the planet's surface, and recovering to lead the Neride 41st Army Regiment.

Tetrarch Remus Ventanus. Credit: Kevin Stillman

In the initial fighting the Word Bearers had seized control of Calth's orbital weapons platform, with First Captain Kor Phaeron turning it on neighboring planets and friendly forces. Leading a small force of his strongest warriors, Guilliman stormed the platform and confronted Kor Phareon. Phareon stabbed Guilliman with a Chaos dagger, hoping to corrupt him as Erebus had Horus, but Guilliman resisted and tore out one of Kor Phareon's hearts. Phearon survived, but the Ultramarines drove the Word Bearers back. Sergeant Thiel managed to destroy the computers the Word Bearers were using to control Calth's defense network and Remus Ventanus and his allies are able to get a Mechanicum data engine up and running to purge the system of Dark Mechanicum scrapcode.

This was, technically, a victory for the Ultramarines. We say "technically" here because well, it's only a victory because the Ultramarines weren't wiped out and managed to survive as a coherent fighting force. Before the planet's defense systems had been reclaimed, the Word Bearers had used them to fire on Calth's star, destabilizing it and starting the process of poisoning the planet. The combatants on the planet's surface were as a result forced to take the battle underground into the planet's tunnels, kicking off the Underground War. As Guilliman departed for Macragge in an attempt to arrive there ahead of a forming warp storm, he ordered Marius Gage to take Macragge's Honour and hunt down and destroy the Infidus Imperator. What followed was the Battle of Macragge's Honour, in which the Ultramarines were ultimately successful in destroying the Imperator but not Kor Phaeron, who escaped into the warp with a retinue of Word Bearer marines, leaving Macragge's Honour adrift with no way to return.

The Ruinstorm and the Unremembered Empire

Following the battle for Calth, Lorgar unleashed his Word Bearers upon the rest of the 500 Worlds, hitting as many places as he possibly could - Espandor, Iax, and others. Lorgar himself traveled to the Fortress World of Armatura, the third-most heavily defended location in the Realm of Ultramar, where he met up with his favorite son, Argel Tal, and Angron. After revealing that he had a pair of extra Furious Abyss class warships and two Gloriana Class Warships (Fidelitas Lex and the Conqueror), Lorgar and Angron went to town on Armatura and then Angron's homeworld of Nuceria, leading into one of the most interesting battles of the Heresy, in which Angron and Guilliman have a back-and-forth about their respective upbringings and how it shaped them. Though a mighty warrior, Guilliman was not a match for two traitor primarchs and was forced to retreat to Macragge while Angron ascended to Daemonhood following the slaughter and warp storms descended on the eastern half of the galaxy.

The Ruinstorm

The Ruinstorm was a massive warp storm created by the Word Bearers - specifically Erebus - via a great ritual performed during the Battle of Calth. The purpose of calling down this warp storm was to cut off the galactic Eastern Fringe and make the warp unnavigable to loyalist forces (Traitor forces could still navigate the warp using secret paths known to Erebus). In addition to cutting off their communications and travel, the Ruinstorm also unleashed hordes of Daemons into realspace to fight alongside the forces of the traitor legions. Ruinstorm Daemons were a new thing to the forces of the Imperium at the time, and they at first these daemons were assumed to be some kind of new xenos threat.

With the Realm of Ultramar bloodied, besieged, and cut off from the Imperium, Guilliman had absolutely no information. Did The Emperor still live? Had Horus reached the Throneworld and cast Him down? Were any loyalist Primarchs still active? Guilliman could not know the answers to any of these questions, but he did have something: An artifact on the planet Sotha called the Pharos.

The Pharos

The Pharos was a Necron artifact made from Blackstone, powered by C'Tan shards, and used for FTL travel and long-distance rapid communication. It's not a single artefact but actually an array of nodes spread across the galaxy, of which the Ultramarines discovered a single, still-functioning node on the planet Sotha. This one was discovered on Mount Pharos, hence the name given to the device (boy, it sure is convenient they found the device in a place that has a vaguely Egyptian name, huh?). The device was discovered by Barabas Dantioch, a still-loyal Iron Warriors Warsmith. Under Guilliman's orders, Dantioch activated the Pharos and tuned it, using it as a kind of smaller, more targeted Astronomicon. By turning it to Macragge, Dantioch was able to create a beacon for navigation in the Eastern Fringe despite the loss of the Astronomicon, allowing more Loyalist forces to come to Guilliman's aid.

The Pharos would eventually be destroyed - overloaded during the battle of Sotha when Dantioch gave his own life to disable the Night Lords fleet. The sudden burst of power created from this overload would ripple across space and eventually call the Tyranid Hive Fleets to Ultramar ten thousand years later.

The Pharos enabled Guilliman to reassert some form of interstellar travel and accordingly, run an empire again. When the Pharos successfully attracted the better part of the Dark Angels Legion, Guilliman finally had another Brother he could share his idea with: Creating a backup empire in case the Imperium of Man ever fell - or if it had already fallen, even. The Lion was not thrilled with this idea (this was heresy, just so we're clear), but the Lion didn't have any better ideas and he had accidentally let Konrad Curze and the Night Lords loose on Macragge. Eventually Sanguinius arrived following the battle of Signus Prime and Guilliman convinced him to serve as Emperor of the Imperium Secundus. This was part of a measured political play by Guilliman - everyone liked Sanguinius, and making him president of the new, cooler Imperium 2 would keep people from thinking this was a power grab by Guilliman on par with what Horus did. It mostly worked.

While the Lion wandered around Ultramar hunting for Curze, the rest of the Night Lords decided to attack the Pharos at Sotha. Despite facing tenacious defenders in the form of Warsmith Dantioch, Captain Alexis Pollux, an Ultramarines Scout named Oberdeii, and some extremely brave members of the Planetary Defense Militia, the Night Lords came close to obtaining control of the Pharos. Dantioch bravely sacrificed his life to stop the Night Lords, and overloaded the Pharos so that the Eighth Legion could not use it. This would later have extremely dire consequences, but only two of the countless trillions of individuals within Imperium Secundus would actually be around to face said consequences later.

Heading to Terra

Eventually, the Lion arrested Curze (after wrecking a chunk of Macragge), and dragged him back to the Throne Room for trial and judgment. Curze told Guilliman 1) The Lion smashed up big chunks of Macragge with orbital strikes and 2) The Triumvirate would not be the ones to kill him, an assassin sent by The Emperor would. Sanguinius had another vision and put two and two together: the Emperor was still alive! This was enough for the three Primarchs to hastily call off their "Imperium Secundus" plan and decide to break out of the Ruinstorm and make for Terra. In order to do this they headed to Davin - the very center of the Ruinstorm - and fought off a massive army of daemons, clearing the way to bust out of the warp storm. The Blood Angels and Sanguinius immediately made for Terra while the Ultramarines and Dark Angels led diversionary attacks to clear a path.

Thanks to the Iron Warriors, the Ultramarines would ultimately arrive too late - by the time they finally reached Terra, the Emperor had been slain by Horus. But while they weren't in time to save the Emperor, they were in time to royally slaughter the Traitors as they fled Terra, take part in a bunch of petty infighting, and later bitter battles to remove entrenched traitors during the period known as The Great Scouring. Under Guilliman's direction, the surviving Loyalist forces focused on recapturing key assets like Luna and Mars, rebuilding their power base instead of chasing after the fleeing traitors.

By the time they'd escaped the Ruinstorm, the XIII Legion had lost more than half their number and had thousands more left incapable of waging battle. Yet they were still the largest, most capable force of loyalists and had the strongest recruitment and supply lines of any legion. It was during this time that Guilliman suggested breaking the Legions into Chapters, each 1,000 warriors strong. This would divide the power of the Space Marines to ensure that another galactic civil war on the scale of the Heresy could ever happen again. In this Second Founding, the Ultramarines would create the largest number of Chapters and, in doing so, go on to become the common ancestor of the majority of operating Chapters in the 41st millennium.

Ultramarines 4th Company Mortis Contemptor

Ultramarines 4th Company Mortis Contemptor

Credit: Alfredo Ramirez

Where to Read More

If you liked this and want to read more about the Ultramarines well good news - there is a lot out there. In particular, they've got great coverage of their time during the Great Crusade and Horus Heresy, and some of the best books in the series star the Ultramarines.

Know No Fear. This Dan Abnett novel covers the Battle of Calth and is probably the favorite among Ultramarines fans reading Heresy novels. If you haven't already read this one, it's a good starting point.
The First Heretic. The story of the Ultramarines during the Heresy is intertwined with the Word Bearers' story and if you want to understand Betrayer and the villains of No Know Fear, you need to read this one. It's also written by Aaron Dembski-Bowden and it's really good.
Macragge's Honour. One of the few graphic novels released by the Black Library, this shows off the space duel between Marius Gage and Kor Phaeron.
Betrayer. Betrayer is ADB's follow-up to First Heretic and Know No Fear, following Lorgar and Angron as they cut their way across Ultramar and clash with Guilliman. The big speech from Angron about fighting the slavers who mutilated his mind? That's in here.
The Honoured and The Unburdened. Rob Sanders' The Honoured continues the story on Calth and details the Underground War. David Annandale's The Unburdened follows much of the same action from the Word Bearers' point of view. Both are more or less novelizations of the campaign laid out in the Betrayal at Calth boxed set.
Unremembered Empire. This Dan Abnett book is divisive among the fans but it's important nonetheless, looking at Ultramarines as empire builders. It also includes a better look at Guilliman's adoptive mother as a character.
Pharos. This Guy Haley novel covers the Night Lords' attack on Sotha, and has some interesting tie-ins with Belasarius Cawl's great work in the more modern lore.

Next Time: The Primarch

That wraps up our look at the Heresy-era lore of the Ultramarines. Next time we'll talk about the lore of the chapter's Primarch, Roboute Guilliman. There's a lot to cover there still and we've tried to keep more of that detail out of this article but there's bound to be some crossed streams. And if there's anything we missed or a book you'd recommend to someone exploring the lore, let us know in the comments below.

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