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@mrfickle

Cant remember where I read it but supposedly a whole legion were subjected to a mind wipe, would explain why the Blood Ravens have no clue about their past if it was them? Maybe they were also called something else prior to the mind wipe? Also they are based right on the fringe away from others and were also cut off for a long while. I am not a lore expert but there are a lot of pointers to say they are something more than they appear.

Also if Horus was told not to talk about the Primarchs that’s something completely separate to what happened to the legions. Also Malcador saying the troops weren’t at fault but it was down do their Primarchs would suggest that maybe the Marines belonging to at least one of the two legions survived, did they go to the Ultra’s or some other Legion? Who knows, or were they renamed and repositioned to the fringe of the Empire to hide them away somewhat?

It also appears very few know about their past and those that do are keeping quiet. Why is their past so shrouded in secrecy, so many questions to be answered about the Blood Ravens LOL.

I think it could have gone something like this:

-Something something 2nd legion Primarch bad, dishonored

-Remaining Marines get mind-wiped and added to the Ultramarines

-Post Heresy, when the legions are split, the survivors are placed into their own chapter, the Blood Ravens (due to the difference of their geneseed, though they are not told)

-They're told their geneseed is from Bobby G

-Centuries later, careful analysis from their apothecaries reveals their geneseed does not match Ultramarines geneseed

Thus, a mystery as to who their Primarch is.

FWIW my view is that nothing could be more dangerous than a rogue primarch. Nothing, except maybe the tyranids.

So, if the emprah did banish all knowledge of them, it meant that there was absolutely no chance whatsoever of them returning to menace the imperium.

If he believed there was a 1 in ten billion chance they might return someday, he'd have kept knowledge of them alive, to guard against the danger they posed.

So, he believed they were permanently gone. That's the logical viewpoint.

Now between 40k and GW logic has a snowball's chance in Hell of actually being how things go. So my bet is that they'll wait till they need something new to keep sales up and then do the X edition in which the lost primarch's return to defeat the imperium and save humanity.

 Pacific wrote:
Thanks Ketara - that's a really interesting summary! Quite a lot in there that I hadn't heard of read before.

-That one of the Primarchs was considered 'Lost' before he was even found by the Emperor.

Why would that Primarch have a status raised in their honour if that was the case? It would have been just 19 statues (going on the short story @ph34r referenced)

I honestly couldn't say. Putting the timeline pieces together, we know that the Emperor knew Unknown Primarch #2 was 'lost' before he was found (likewise, Guilliman's comment reinforces that he didn't actively betray/turn on the Emperor). It's almost certain that his Legion was merged into Guilliman's (two references in-series). And as you say, the conversation with Malcador implies that he certainly didn't perish in a dishonourable way.

We could devise many scenarios. For example, perhaps he died leading a coalition of humans against a Xenos threat, and his death rippled through the Warp? Perhaps he was killed so that Malcador or another high ranking contact could escape a mutual foe? I could come up with other reasons, but it's clearly plausible. We just don't have any other pieces right now to go off to add detail.

I suppose the Graham McNeil/Laurie Goulding fan campaign/narrative piece could tie up with Rangdan. Given a choice between execution and death in battle 'Mal' (as his friends call him) is allowed a final assault on that species as part of that campaign.

I read quite an interesting piece once about Feudal Japan, where disgraced nobility and their wards were allowed to carry out a suicidal charge in battle as an alternative to Sepuku. Perhaps something like that?
That would also explain Horus' (quite angry) reaction to Malcador removing their statues, if they were perceived to have been lost or defeated in some honourable fashion (or something that he, as a warrior, deemed honourable).
He would hardly have had that reaction if the other Primarch had been treasonous, or had just been some 'foe' at the head of an alien empire that had fought the Emperor rather than side with him (although in that instance he wouldn't have had a status there in the first place).

Vulkan's reference to a 'Sanction' and Sanguinius' fear of destruction from biological imperfection come from the mysterious Missing Primarch #1 (or 'Mal'). Given that we have a time period/war for his destruction (the bio-taint of the Rangdan), it's not a stretch to link it all together. So I completely agree.

We know that the Emperor deployed the Dragon to finally settle the Xenocides, but as you say, a suicide run from the infected legion would be a perfect glorious finish for them. Perhaps as cover, or perhaps to smuggle the Dragon in? Who knows. A sacrifice like that would certainly cement his place of honour in the other Primarch's memories. Given that it would have involved the destruction/tainting of a Legion in the early days of the Crusade though, it wouldn't be a sacrifice the leadership would want widely known.

@Matt Swain

Or maybe the Blood Ravens Primarch read the Emperors and Malachors minds and discovered that once humanity was restored, the Primarchs and Astartes were expendable?I read somewhere that once this happened that’s exactly what the Emperor had planned, hell he was even gonna sacrifice Magnus to the throne until Magus screwed it up.

Maybe the BR Primarch foresaw what was coming due to his ability to read minds, saw the Emp was gonna stitch him possibly (maybe he was the first choice before Magnus was?) and thought I am off and went off into the galaxy fringe with some of his most loyal troops, this could also be a reason for knowledge found on Eldar planets in the Eye of Terror? The Emperor realising one of his sons had forsaken him struck him from the records?

Maybe another version could be he was going to use the Necron monolith to change the course of things but it didn’t turn out as planned and he was lost into some webway? Or maybe happily went off with the Eldar who he maybe saw not as offensive to humanity as the Emperor?

Also the Emperor may have purged him from the records but that doesn’t mean he isn’t aware of his existence or others within the Imperium as there is obviously some who know exactly the origin of the Blood Ravens. Maybe the Emp was going to deal with him once the human webway was operational but Magnus’s curveball coupled with Horus’s attack on Terra screwed things up?

Or maybe he discovered stuff he shouldn’t have known and the Emp has him held in stasis under the golden palace and made some BS story of him leaving on some unsanctioned mission and lost to the warp, no Primarch = no Legion = both expunged from records.

Another weird point is the Grey Knights having an affinity for the Ravens, and close links with the Malleus and Mechanicum, what’s that all about?

Crazy thing about these 2 lost Primarchs is that counter positions can be offered from both sides of the fence.

Ultimately I think GW should shed light on the matter, maybe like you say, when they need a bit of reinvention to boost income, that may be just what happens

From a potentially ignorant perspective I think that falling to Chaos is not likely to have been a reason. If so the Emperor would have been more on his guard against Chaos taint in the other Primarchs.

As mentioned above either some failure in some mission or that they did in some form not measure up to the standards the Emperor had set for the Primarchs seems more likely. Insubordination could also have been a reason for their eradication.

 Chimaera wrote:
@Matt Swain

Or maybe the Blood Ravens Primarch read the Emperors and Malachors minds and discovered that once humanity was restored, the Primarchs and Astartes were expendable?I read somewhere that once this happened that’s exactly what the Emperor had planned, hell he was even gonna sacrifice Magnus to the throne until Magus screwed it up.

Maybe the BR Primarch foresaw what was coming due to his ability to read minds, saw the Emp was gonna stitch him possibly (maybe he was the first choice before Magnus was?) and thought I am off and went off into the galaxy fringe with some of his most loyal troops, this could also be a reason for knowledge found on Eldar planets in the Eye of Terror? The Emperor realising one of his sons had forsaken him struck him from the records?

Maybe another version could be he was going to use the Necron monolith to change the course of things but it didn’t turn out as planned and he was lost into some webway? Or maybe happily went off with the Eldar who he maybe saw not as offensive to humanity as the Emperor?

Also the Emperor may have purged him from the records but that doesn’t mean he isn’t aware of his existence or others within the Imperium as there is obviously some who know exactly the origin of the Blood Ravens. Maybe the Emp was going to deal with him once the human webway was operational but Magnus’s curveball coupled with Horus’s attack on Terra screwed things up?

Or maybe he discovered stuff he shouldn’t have known and the Emp has him held in stasis under the golden palace and made some BS story of him leaving on some unsanctioned mission and lost to the warp, no Primarch = no Legion = both expunged from records.

Another weird point is the Grey Knights having an affinity for the Ravens, and close links with the Malleus and Mechanicum, what’s that all about?

Crazy thing about these 2 lost Primarchs is that counter positions can be offered from both sides of the fence.

Ultimately I think GW should shed light on the matter, maybe like you say, when they need a bit of reinvention to boost income, that may be just what happens

Just like he did with the thunder warriors, I have wondered if one of the primachs discovered the fate of the thunder warriors and realised that the astartes were just tool to be used and disposed of.

However I am not sure that is the truth for primarchs. I think the astartes were only created in response to the lost primarchs. I think the primarchs were originally planned to lead the imperial guard and once they disappeared astartes were plan b and then luckily, or so he thought, the emperor got plan b and plan a to work together.

Just like he did with the thunder warriors, I have wondered if one of the primachs discovered the fate of the thunder warriors and realised that the astartes were just tool to be used and disposed of.

I think this ties into a common complaint with the way the Heresy story developed.

There was a real potential for there to be a causality behind the Heresy that tied into the fate of the Thunder Warriors. Like you say, that they were a tool that were disposed of once their usefulness was done.
It would have been easy to tie this in with the travails of the Great Crusade. Thousands of Astartes living and dying over hundreds of years for an Imperium (and an Emperor?) that just saw them as tools and something that had no place in a peaceful galaxy, should that ever have been achieved.
What we would have then had was a real meat on the bones of the story, a real reason for rebellion.

Instead, the series veered very much towards science fantasy (and unfortunately that dreadful trope of 'A wizard did it' - please look this up if you don't know the reference) where the Imperium being split in two, the galaxy set aflame, because Horus got stabbed by a magic sword - he saw future stuff, and then you've got that massive causal leap of whatever dreams he had being strong enough to undo hundreds of years of following his father and being part of that system.

I quite liked the Laurie Goulding story posted above as it veered a little bit towards the former. Perhaps the Emperor (or Malcador at least) was a bit of a cad, and thought that the Primarchs (and by extension the Astartes) should know their place? He drove the Warmaster of the Imperium's armies, one of the most powerful warriors in the galaxy who had armies of millions following his lead, down to his knees - almost slew him - over the utterance of a name. That really showed who was boss!
How might that story have reverberated with the other Primarchs that saw Horus treated in this way, not to mention Horus' humiliation? You can imagine, as they hear word that another ten thousand legionnaires have been slain on the far rim of the galaxy, their passage unremembered and unheralded by the fat aristocrats and administratrum that nestled safely and comfortably in Sol.

That very much comes back around to the 'better to rule in hell than serve in heaven' message, the Paradise Lost quote that was (at one time, apparently) meant to have served as Horus' motivation to turn against his father in the original Heresy fluff. It's a shame there wasn't a little bit more of it in the series, and something that could pull in characters with emotions of betrayal and fear that you could relate to, rather than two-dimensional 'evil' demons whispering lies into their ears.

Absolutely. This was a huge misstep in the Horus Heresy novel series, and a real let down. Horus is basically removed as a character from the point when he gets stabbed with the magic knife. At that point, he no longer has motivations, he is just Evil. All character development is abandoned for a fast forwarded descent into madness, and then the whole thing slows down massively to mess around.

It would have been so much better to have proper motivations for Horus, especially at first, and a much more gradual "corruption". They laid a lot of good groundwork in Horus Rising, and these themes are often referenced at other points, so it is obvious they were thinking about it, but then they seem to have backed off that stuff and gone for a much more cartoonish plotline unfortunately. Ah well. My headcanon version of the Heresy follows along the lines you outlined Pacific.

 Pacific wrote:
@The_Grim_Angel - I'm not sure to be honest. I think it would have had to be something so awful that their memory was censured. I suppose the stuff about Malibron would line up with that if it were canon; He used exterminatus on a defenseless world that had already surrendered (in a fit of pique?) which would otherwise have been brought into the Imperium and also stole dark age/forbidden tech for cloning technology to rebuild his legion. The large volume of Marines lost in that conflict would explain where the rest of the Space Marines went (we know from other HH books that some of the Legions were swelled with members of disbanded Legions, although it is presented as a rumour). Although otherwise we don't know anything about the lost Primarch or his Legion.
[…]

I don't disagree with you, because I think you are in some way right; in fact what I described isn't the story about the eleventh primarch I'm working on. It was the concept that I started from, to develop my story about the eleventh primarch and I decided to drop that concept (in the way it was formulated here) because it creates too many inconsistencies with the canon, so I started to develop a new and improved concept; for the second primarch I have other plans and I am quite pleased by the fact that other users expressed my same ideas in this thread.
About the concept of Maliborn, I think the Games Workshop decided to drop that idea both because it is too similar to the story of Konrad Curze and the destruction of Nostramo, than because they found out that it is better for the lore to keep the mystery around the fate of the two lost primarchs, than reveal why they were expunged.

I have found an interesting hint about the two erased primarch: it seems that in the novel "The Horus Heresy; book 1: `Betrayal`" it is stated that the name of the second primarch has more or less the same length of Alpharius and the name of his legion is barely shorter than "Emperor's Children", while the name of the eleventh primarch is about the same length of Magnus "The Red" and the name of his legion is around the same length of "Thousand Sons". If that is true, Maliborn should be the name of the second primarch.

I think maybe one of the Lost Primarchs, the one involved with the Ymga Monolith, might have intuited the extent of the Necron threat. I don't think even the Great Crusade could have dealt with a fully awakened Necron Empire. It's a definite blow to the Emperor's plan to shield Humanity from Chaos when the extinction of Humanity at the hands of the soulless Necrons was the other option.

Remember how Lorgar failed the Emperor? He failed by not conquering fast enough. The religious thing, sure, definitely not great, but the real problem was that Lorgar was lagging behind his brothers in terms of Conquest. Perturabo conducted a decimation of the Iron Warriors because they were behind other legions that had already recovered their Primarchs when he was given their command. A nigh-lunatic action to waste the lives of thousands of Astartes for no gain whatsoever except punishment for not being the best.

A failed Primarch is one that failed to fulfill his purpose and conquer the galaxy for the Imperium of Man. And why would someone do that if it awakened the dormant Necron threat and wiped everyone out?

Remember, it's Warhammer, imagine the worst that could happen and it's probably worse than that.

I didnt expect this topic to get so many replies! i learned so much with this. thanks everyone thats replying to it!

I was wondering if those this thread should be merged with this Accepting Head Canon, Vol 3 - Missing Primarchs Boogaloo: de facto they are about the same topic.

 Da Boss wrote:
Absolutely. This was a huge misstep in the Horus Heresy novel series, and a real let down. Horus is basically removed as a character from the point when he gets stabbed with the magic knife. At that point, he no longer has motivations, he is just Evil. All character development is abandoned for a fast forwarded descent into madness, and then the whole thing slows down massively to mess around.

It would have been so much better to have proper motivations for Horus, especially at first, and a much more gradual "corruption". They laid a lot of good groundwork in Horus Rising, and these themes are often referenced at other points, so it is obvious they were thinking about it, but then they seem to have backed off that stuff and gone for a much more cartoonish plotline unfortunately. Ah well. My headcanon version of the Heresy follows along the lines you outlined Pacific.

I love the Horus Heresy as a setting, and most of the novels I've read were great - but I do strongly agree with you on this point. I always thought that Horus went from competent Warmaster to "mustache-twirling evil guy" really, really quickly over the course of that first trilogy of novels. Like... it wasn't subtle. At all. And Horus was supposed to be this super charismatic leader and commander that everyone looked up to. Suddenly he's making moves like a cartoon villain.

The Blood Ravens being a successor is certainly possible but correct me if I am wrong, wasn’t there some short story or reference to Magnus the Red ordering any surviving Thousand Sons to hide after the attack on Prospero? I also believe there was an order or chapter of the Thousand Sons that were called Ravens and used a very similar symbol? Might be mixing it up with something fan made so please correct if I am mistaken.

Like the idea that there are successor chapters to the Ultras and Imperial Fists that are made up of the missing primarchs gene-seed, since they both seemed to have accepted them after the loss of the primarchs. But this brings up an interesting point, the two lost legions gene-seed must be very similar to the Ultras and Fists, with only the Fists having loss the use of two organs I believe. So the idea that these lost legions were tainted seems less likely, more that they were infected or altered by the actions of their respective primarchs.

I also love the idea that Horus was meant to follow more in line with Lucifer from Paradise Lost. What I remember most about the book is in the very beginning Lucifer and the angels are told to spend eternity to burn in the lake fire, and it is Lucifer who is the first to literally leave the lake and rise up. The other angels follow suit and the realization hits them that they don’t have to follow Gods rule anymore, they are too far from him and heaven. If Horus’ story was more about self discovery and enlightenment due to his absence from the Emperor, could have been more interesting. Then the question becomes did Horus choose his fate or was pushed towards it? It can be easier for the readers to empathize with someone who made a huge up, over being manipulated by gods of emotions haha

I also have found it maddening trying to figure out what the two lost legions were experts in and what aspect of the emperor they embodied. What purpose or specialty could they have possibly employed that wasn’t already established with other 18 legions? I theorize that one legion could have been experts in the warp or void warfare and psychers, and the other has some connection chemical or biological warfare. It seems that the legions were almost grouped in pairs when it came to tactics and this is all I can think of.

 Mr. Grey wrote:

 Da Boss wrote:
Absolutely. This was a huge misstep in the Horus Heresy novel series, and a real let down. Horus is basically removed as a character from the point when he gets stabbed with the magic knife. At that point, he no longer has motivations, he is just Evil. All character development is abandoned for a fast forwarded descent into madness, and then the whole thing slows down massively to mess around.

It would have been so much better to have proper motivations for Horus, especially at first, and a much more gradual "corruption". They laid a lot of good groundwork in Horus Rising, and these themes are often referenced at other points, so it is obvious they were thinking about it, but then they seem to have backed off that stuff and gone for a much more cartoonish plotline unfortunately. Ah well. My headcanon version of the Heresy follows along the lines you outlined Pacific.

I love the Horus Heresy as a setting, and most of the novels I've read were great - but I do strongly agree with you on this point. I always thought that Horus went from competent Warmaster to "mustache-twirling evil guy" really, really quickly over the course of that first trilogy of novels. Like... it wasn't subtle. At all. And Horus was supposed to be this super charismatic leader and commander that everyone looked up to. Suddenly he's making moves like a cartoon villain.

Another disappointment, I think, was how they handled the Sons of Horus "warrior lodges" and how almost the entire first trilogy is written from the POV of Sons of Horus characters who conveniently aren't part of them and actually stay loyalist. My impression after the first read was that it was an easy way to circumvent exploring the motivations and thought processes of the majority of Sons of Horus who turned against the Emperor and became team-killers at Istvaan. It would have been great to have at least a couple of POV chapters on how things unraveled inside the lodges. The whole corruption process was done besser with the Emperor Children in "Fulgrim". I'd say.
Angron and the World Eaters, I didn't mind much, as they were already nuts when still part of the Great Crusade.

For the Emperor!
I started a warpstorm: in this topic we are talking about the successor chapter of the traitor legions and in the tread dedicated to the successor chapter of the traitor legions we are talking about the two lost primarchs.

Musselman wrote:
The Blood Ravens being a successor is certainly possible but correct me if I am wrong, wasn’t there some short story or reference to Magnus the Red ordering any surviving Thousand Sons to hide after the attack on Prospero?

I don't remember that story, but it is plausible that Magnus give a similar order, after what happened to Prospero. Anyway we know for sure that at leas one loyal Thousand Son survived (Janus), because he became the first Gran Master of the Grey Knights.

Musselman wrote:
I also believe there was an order or chapter of the Thousand Sons that were called Ravens and used a very similar symbol? Might be mixing it up with something fan made so please correct if I am mistaken.
[…]

In the Thousand Sons there was the Corvidae Cult composed by psykers skilled in the discipline of precognition and divination and that cult used a raven head like symbol.

For now I will not answered to the cut part, because I need to think about what you have written.

Automatically Appended Next Post:

Musselman wrote:
[…]
Like the idea that there are successor chapters to the Ultras and Imperial Fists that are made up of the missing primarchs gene-seed, since they both seemed to have accepted them after the loss of the primarchs. But this brings up an interesting point, the two lost legions gene-seed must be very similar to the Ultras and Fists, with only the Fists having loss the use of two organs I believe. So the idea that these lost legions were tainted seems less likely, more that they were infected or altered by the actions of their respective primarchs.
[…]

Maybe I'm wrong, but it seems to me that the Imperial Fists loss the use of two organs only after some time (millennia?) of degradation of their geneseed.

Musselman wrote:
[…]
I also have found it maddening trying to figure out what the two lost legions were experts in and what aspect of the emperor they embodied. What purpose or specialty could they have possibly employed that wasn’t already established with other 18 legions? I theorize that one legion could have been experts in the warp or void warfare and psychers, and the other has some connection chemical or biological warfare. It seems that the legions were almost grouped in pairs when it came to tactics and this is all I can think of.

Like I already wrote it seems that the name of the second primarch was approximatively as long as Alpharius and the name of his legion was just shorter than Emperor's Children. So, because the second primarch should have been a powerful psyker (at the same level of Magnus), I'm starting to wonder if it could be plausible that Maliborn was meant to be the second primarch, if his legion's purpose was built the Imperial Webway while the Emperor was absent and if he had also the duty to run the astronomican; or to defend the Imperial technicians who was building it. If this theory (I must still verify if it is plausible), we can suppose the second primarch was lost in the warp during a suicidal mission ordered by the Emperor (in this case their records would have been expunged to protect the Emperor mith), or to escape from the Emperor's wrath, due to an irreconcilable quarrel among them.
If I am right, I already thought a name for the second legion: "Empyrean Pioneers".

I also have a headcanon theory that at least one lost Primarch had specialized and limited psyker abilities.

When you look at how Magnus had mastery of all psyker disciplines, and how Sanguinius and Kurze had divination in their "pocket", how Lorgar had telepathy, divination and telekinesis, my headcanon says that one lost Primarch was proefficient in other Psyker disciplines than Sanguinius, Kurze or Lorgar. So pyrokinesis, fulmination, biomancy and geokinesis would have been possible Psyker disciplines they were proefficient in.

And then one would have been full blown Psyker like Magnus and he and his legion were corrupted by forces of the Warp and that's why the Emperor had his attitude towards Magnus and Thousand Sons using Psyker powers. Because he had seen a Legion and Primarch get corrupted and mutated by powers of the Warp to something really bad. Like a legion with incidents like Red Thirst episodes and Black Rage incidents happening publicly quite often leading to loss of life. So they were purged.

 Ketara wrote:
To pull out from an earlier dissection of mine on the Missing Primarchs:-

[…]
- Both were destroyed in between the years 30,840 (the Finding of Lion El'Jonson) & 31,560 (The Drop Site Massacre). This means that one of them was potentially destroyed before the finding of Perturabo, Mortarion, Curze, Angron, Lorgar and the Khan.
[…]
-That one of the Primarchs was considered 'Lost' before he was even found by the Emperor. We know this because the Emperor dismissed two of the Primarchs as being a bad subject matter when he found Corax, even though he'd only found one of the Missing Primarchs at that time (according to the official BL order of finding leaked by Laurie Goulding).
[…]

[…]

The obliteration of the second and of the eleventh primarch should have take place shortly after the finding of Lion El'Jonson (848M30), because Mago (Centurion of the Eighteenth Company of the World Eaters) said during the Ghenna Massacre (900M30): "This road will kill us all. Everything we are -- the brotherhood, the nobility -- all of it will be erased. History will never know what we once were, only what you would have us become. A horde of marauding berserkers, driven by nothing save the impulse to spill blood. Reavers and murderers, not warriors. How long do you think you can live as monsters before you force the Emperor to act? How long before the Eaters of Worlds join the others, the forgotten and the condemned?"
So we can be reasonably sure about when they were been expunged and we can also state only one of them was condemned/purged by the Emperor, while the other was lost/forgotten for some reason, but he wasn't a traitor.

On a related note: What do you believe happened to Valdor?

Blood ravens are pretty cool, i might use them for a loyalist sm chapter if i ever did one.

As to tracing their origins to the Ksons, well, their armor is red like the original ksons were, and they seem to go psyker heavy, but that's about it.

As to why the two primarchs are lost to history, maybe it has to do with the 'true name' thing. In magic and in 40k to an extant knowing somethings true name gives you some power over it. This seems true of daemons in 40k. Maybe the missing primarchs were hidden to keep chaos from learning their true names and having power over them.

The_Grim_Angel wrote:

 Ketara wrote:
To pull out from an earlier dissection of mine on the Missing Primarchs:-

[…]
- Both were destroyed in between the years 30,840 (the Finding of Lion El'Jonson) & 31,560 (The Drop Site Massacre). This means that one of them was potentially destroyed before the finding of Perturabo, Mortarion, Curze, Angron, Lorgar and the Khan.
[…]
-That one of the Primarchs was considered 'Lost' before he was even found by the Emperor. We know this because the Emperor dismissed two of the Primarchs as being a bad subject matter when he found Corax, even though he'd only found one of the Missing Primarchs at that time (according to the official BL order of finding leaked by Laurie Goulding).
[…]

[…]

The obliteration of the second and of the eleventh primarch should have take place shortly after the finding of Lion El'Jonson (848M30), because Mago (Centurion of the Eighteenth Company of the World Eaters) said during the Ghenna Massacre (900M30): "This road will kill us all. Everything we are -- the brotherhood, the nobility -- all of it will be erased. History will never know what we once were, only what you would have us become. A horde of marauding berserkers, driven by nothing save the impulse to spill blood. Reavers and murderers, not warriors. How long do you think you can live as monsters before you force the Emperor to act? How long before the Eaters of Worlds join the others, the forgotten and the condemned?"
So we can be reasonably sure about when they were been expunged and we can also state only one of them was condemned/purged by the Emperor, while the other was lost/forgotten for some reason, but he wasn't a traitor.

If it’s the WE then it sounds like one of the lost chapters we’re a bunch of psychos, maybe they were the first ones to just clear out a planet of all life regardless of loyal or not, in order to achieve thier goal

I've always had the notion that one of the Lost Primarchs was a committed democrat. Democrat with a small 'd', please note.

The Emperor just could not deal with one of his sons who was not willing to submit to his authority.

The_Grim_Angel wrote:

The obliteration of the second and of the eleventh primarch should have take place shortly after the finding of Lion El'Jonson (848M30), because Mago (Centurion of the Eighteenth Company of the World Eaters) said during the Ghenna Massacre (900M30): "This road will kill us all. Everything we are -- the brotherhood, the nobility -- all of it will be erased. History will never know what we once were, only what you would have us become. A horde of marauding berserkers, driven by nothing save the impulse to spill blood. Reavers and murderers, not warriors. How long do you think you can live as monsters before you force the Emperor to act? How long before the Eaters of Worlds join the others, the forgotten and the condemned?"
So we can be reasonably sure about when they were been expunged and we can also state only one of them was condemned/purged by the Emperor, while the other was lost/forgotten for some reason, but he wasn't a traitor.

Let's pin it down a bit more. The Goulding list of discovery was as follows:-



El' Jonson was found in 848.M30. The second Xenocide was 862-882, whilst third Rangdan Xenocide was in the 890's. The quote you give is in 900. Corax can't have been found any earlier than 865, as that was when the Khan was found (and he's a few Primarchs above Corax in the discovery order).

Working on the (firmly established) basis that the first Missing Primarch died in the Xenocides, this makes it likely that he died in the second Xenocide. It might also explain why the Space Wolves had the experience of fighting tainted brothers (the remnants of his tainted legion might have survived on the Rangda side to the third Xenocide). The II Legion Primarch would also be the likely candidate for being the 'forgotten' one, as the survivors of the second Xenocide were generally sworn to secrecy.

That in turn makes it likely that our second unknown Primarch, the one who was 'lost' before he even joined the Imperium, would be classified as the 'Condemned'. If the date you've cited is correct, he clearly died in between Corax's finding date, and 900. M30. So the two died anything between ten to thirty years apart in (roughly) 870-900.M30. The first Missing Primarch likely (this is now rough speculation) at the culmination of the Second Xenocide in 882.M30, and the second Missing Primarch between 883-899. M30.

It’s something I’d rather see them just leave alone, and not explore any deeper. With the hit and miss nature of the fiction, the odds are just too high that any ‘big reveal’ will just be sales fodder, and deeply disappointing narratively. Some things are better left to speculation.

On this timeline from the events of the Great crusade,

https://warhammer40k.fandom.com/wiki/Great_Crusade_Chronology

it mentions two events in M30.965 and M30.969, had all data redacted and the involvement of the Space Wolves in both. This is also after the Night of the Wolf event where the Space wolves fought the World Eaters so this is not one of the two. I always took that as being the final purges of the lost legions, perhaps both legions were destroyed separately or just needed two massive battles to finally destroy the marines and the Primarch.

I still believe that the 2nd was lost first but not sure if it was the Rangda or something else. I always go back to the mention of the Ymga monolith and the campaign that the 2nd led. It could be just a random mention with no real intent, but feels like it could be important due to the importance of Necron tech against the warp. Would think the Emperor had to have had a plan to deal with chaos gods and the necrons, and to have one of his sons investigate said tech would be useful and dangerous. Maybe the 2nd was declared lost by the emperor only to have the 2nd re-emerge years later under great suspicion or even mutated to the point that full purges were required.

 Ketara wrote:
[…]
Let's pin it down a bit more. The Goulding list of discovery was as follows:-

Spoiler:

[…]
Corax

[DELETED FROM IMPERIAL RECORDS]

Alpharius

El' Jonson was found in 848.M30. The second Xenocide was 862-882, whilst third Rangdan Xenocide was in the 890's. The quote you give is in 900. Corax can't have been found any earlier than 865, as that was when the Khan was found (and he's a few Primarchs above Corax in the discovery order).
[…]

There is an inconsistency among the sources: in the novel "Deliverance lost" the Emperor say to Coras he has 17 brother and Corax ask how it can be possible, because he know he has 19 brother, then the Emperor, with a "bleak and filled of deep sorrow" face answers: «This is a conversation for another day». This suggest Corax was found after the obliteration of the two lost primarch.

The_Grim_Angel wrote:

 Ketara wrote:
[…]
Let's pin it down a bit more. The Goulding list of discovery was as follows:-

Spoiler:

[…]
Corax

[DELETED FROM IMPERIAL RECORDS]

Alpharius

El' Jonson was found in 848.M30. The second Xenocide was 862-882, whilst third Rangdan Xenocide was in the 890's. The quote you give is in 900. Corax can't have been found any earlier than 865, as that was when the Khan was found (and he's a few Primarchs above Corax in the discovery order).
[…]

There is an inconsistency among the sources: in the novel "Deliverance lost" the Emperor say to Coras he has 17 brother and Corax ask how it can be possible, because he know he has 19 brother, then the Emperor, with a "bleak and filled of deep sorrow" face answers: «This is a conversation for another day». This suggest Corax was found after the obliteration of the two lost primarch.

I've run into this before and addressed it above. It's not actually an inconsistency. All it means is that the Emperor knew that one of his sons ('the condemned') was lost to him before he was 'found'. The Emperor could know that through intercepted communications, warp signature, rogue trader sources, or any number of other things.

For example (imaginary scenario), the 'Condemned' might have been a psychic that was found criminally guilty of something in a surviving human empire; who then got lobotomised and wired into a machine make a mini-Astronomican or something for them. The Emperor found out through both his own senses and information communicated by informal contacts before he sent the marines in to conquer the place. The result? Corax is technically 'found' before the 'Condemned' was ; but the Emperor still knows what happened and knows that the 'Condemned' is lost to him in order to communicate it to Corax.

 totalfailure wrote:
It’s something I’d rather see them just leave alone, and not explore any deeper. With the hit and miss nature of the fiction, the odds are just too high that any ‘big reveal’ will just be sales fodder, and deeply disappointing narratively. Some things are better left to speculation.

I kind of agree..

We have already read far more about them than was originally envisaged. Rick Priestly said that it was meant to be something that had happened so long ago that even the names of heroes and Primarchs are mixed up and forgotten, it was literally just the time of legend.

Also, if any new official update now, it will almost certainly be that Cawl travelled back in time to create himself, and ensure his name spreading through and overwhelming every single piece of 40k lore, even the bits that happened thousands of years before he existed.