Heresy timeline in Betrayal at Chondax - at odds with established lore?

[Xenith]

Firstly, if you havent downloaded the page from the Black Books, go do so now, the Chondax section from Malevolence is 18 pages of amazing fluff:

https://www.warhammer-community.com/en-gb/articles/9wh4zb5f/pages-from-the-black-books-the-betrayal-at-chondax/

 

Secondly, I wanted to discuss the timeline presented in this lore, as it seems a bit off, especially considering it was from Malevolence, which was released in 2019, well after the heresy series was winding down, and timeline well established. A few select quotes are below a bullet point summary. 

 

The Chondax lore says:

 

• Chondax happens post-Ullanor 
• Horus begins to position not-totally-loyal-to-him legions in dangerous or out of the way warzones - WS to Chondax, BA to Signus. 
• Alpha Legion sent in advance of the WS to lay a trap "before the end of the great triumph at Ullanor", with enough time to build multiple space stations and listening posts. 
• This was 4 years before Isstvan, 3 years before Davin
• Word bearers assisted the alpha legion with warp magic to shut down communications
• Prospero happened while the Scars were held up in Chondax
• The AL had >600 capital ships in the system, and up to 30,000 legionnaires. 
•  

Quote

In the ruins of the last great threat to Mankind’s dominance [the orks at Ullanor], and the last real challenge to the Great Crusade, Horus drafted a number of orders. Regiments of the Imperial Army and Titan Legions were re-organised and redeployed at his command. Those units whose loyalty to the new Warmaster was absolute saw themselves shifted to key strategic positions, while those with little personal loyalty to Horus were posted to the most bloody of the Great Crusade’s war zones

 

Quote

Unlike some of his brothers, Jaghatai Khan, was one of the Primarchs that the new Warmaster counted as a ready ally, whose rough honesty and disdain for subterfuge put him out of suspicion as a rival to the great destiny Horus nurtured in the dark corners of his soul.

 

Quote

The Alpha Legion also received orders to depart for that otherwise insignificant stretch of space, but for a cause far removed from the business of the Great Crusade. Horus would need the appropriate instrument to set his trap, to bait it and, at the right moment, snap its jaws shut

 

Quote

This was the first year of the 31st Millennium, four years before the massacres in the Isstvan system and three years before Horus’ encounter on the moon of Davin. Far before most contemporary accounts consider the madness of the Horus Heresy to have begun, and yet it seems that the actions of various malignant groups active within the Imperium had already planted the seeds of treachery within the hearts of many of the Emperor’s greatest servants.

 

 

Now, this goes against my thinking (im sure from the HH series) that he timeline went

1. Monarchia, Lorgar seeks out the primordial truth, begins to spread lodges through other legions
2. 50 years later - Horus declared Warmaster at Ullanor
3. Ullanor +1 year - Luna Wolves renamed Sons of Horus
4. Davin
5. ~X years pass, in which Horus sends the WS to Chondax, BA to Signus, the UM and DA to the far side of the galaxy
6. Prospero
7. Isstvan III
8. Isstvan V
9. Scars released from Chondax

 

The 2019 Malevolence timeline has Horus already begin to want the throne at Ullanor, and Chondax/Signus being a year before Davin, which seems odd.

 

Has the Malevolence author got it wrong, or am I mistaken in my rough timeline above?

Edited July 11 by Xenith

[Antarius]

I was definitely of the impression that Horus was Warmaster for some time, before turning to Chaos and he was only named Warmaster at the triumph of Ullanor. So yeah, I'd have to say there's something a little wonky about that timeline.

Now, I could see the WB and possibly the AL being up to treacherous stuff before that, but I think things fall apart somewhat if it's happening at Horus' direction - and while timelines can be stretched and bent somewhat, as well as retconned slightly, I think if Horus is a traitor before Davin, it sort of robs his story of its essential tragedy.

Edited June 28 by Antarius

[SvenIronhand]

3 hours ago, Antarius said:

Now, I could see the WB and possibly the AL being up to treacherous stuff before that, but I think things fall apart somewhat if it's happening at Horus' direction - and while timelines can be stretched and bent somewhat, as well as retconned slightly, I think if Horus is a traitor before Davin, it sort of robs his story of its essential tragedy.

I'm pretty sure the Black Books make mention of things like that.

Edited June 28 by SvenIronhand

[No Foes Remain]

You also must remember that the Black Books are written from a post-heresy Imperial view, so what happened to our out-of-verse knowledge and view isn't what they thought happened. In Inferno there was a reference to Magnus only teleporting a single Thousand Son (implied to be Ahriman) and the rest were just 'copies' made by Magnus' will during the fight, which is not true as we - the readers - know different but the Imperial scribes don't and may be guessing on what they think they know. Which is bugger all.

[Felix Antipodes]

In the end the HH novels are the official timeline of the setting (to me).  The Black Books are set up as being by an Imperial historian giving his version of what happened after the event, so can verify the information within the novels or diverge because of lost information, guesswork, or political agendas.  Anything that paints Horus as an even bigger bastard would be encouraged in the aftermath in my view.

[lansalt]

Malevolence also included a full Custodes army fighting with the BA at Signus Prime. Something that never happened in Fear To Tread.

Suffice to say, the Black Books are not always the best source for accurate information about the HH. Besides a bias on promoting FW models, they have parts with very dubious canonicity.

[Xenith]

All good stuff thanks! Easy to forget that this is from a chroniclers point of view - I haven't read the full first book! There's definitely a lot of speculation in there.

[Blissful Brushes]

I think Ullanor is 000.M31, Istvaan III is 005.M31 and Davin is 004.M31 so you’ve got 4 years of Horus being happy smiley Warmaster, a year of him brewing his heresy and I’d put the revelation of the betrayal at 005.5.M31 with Istvaan V probably being close to being a lovely Christmas event unless they’re managing to Marshall 7 legions inside a month.

 

Whole Heresy is a 7 year gig.

 

I think that you have to take established timelines with a big grain of salt if you want to think about things on a practical level. I should think even with warp travel and campaigns being resolved instantly the Heresy should probably be a massive initial coming together and then a 70 year campaign culminating in Terra.

[Tymell]

I have full timeline notes across the entire series available here if of use: https://sites.google.com/site/tymellsheresy/horus-heresy-timeline-notes-potential-spoilers

 

I've marked existing instances of apparent contradictions in red, and as you can see, there are a lot of those in Malevolence. Specifically, the points I noted on my original reading of Malevolence:

• The book states that the initial compliance of Signus was in 933, 1 decade after the humbling of the Word Bearers at Monarchia. However, Monarchia happened in 963. Given that the Word Bearers apparently sowed seeds of Signus' eventual fate during its compliance, the "one decade after Monarchia" point is more likely accurate, so 973 seems most likely.
• The Alpha Legion apparently received their orders (from Horus) for Chondax long before Jaghatai did. This makes little sense though, as Horus wasn't yet corrupted, or even Warmaster, by that point.
• "7 years had passed since their arrival" when word of the Heresy reached the White Scars. Likely a bit of an exaggeration since they only arrived in early/mid-001, and this happened in early 007.
• Jaghatai was discovered in 865, and would wait "nearly a decade" for most of the pioneer companies to gather at his call. Their first engagement together was the Kolarne Circle, which took 5 years. However, this conflicts with what is shown in Warhawk of Chogoris.

So yes, I would say that issues you're seeing are errors that the original author(s) made.

 

To cover the points you mentioned Xenith, from those notes:

1. Monarchia
   • 29,963
2. 50 years later - Horus declared Warmaster at Ullanor
   • 30,000
3. Ullanor +1 year - Luna Wolves renamed Sons of Horus
   • 30,003
4. Davin
   • early 30,004
5. ~X years pass, in which Horus sends the WS to Chondax, BA to Signus, the UM and DA to the far side of the galaxy
   • Sort of: Horus does dispatch the Lion, Sanguinius and Guilliman to Thramas, Signus and Calth, respectively, over this period (specifically in 30,005 I believe). Though Chondax starts earlier, that one begins shortly after the Triumph at Ullanor (Jaghatai is specifically hunting down Orks that fled from that victory, IIRC).
6. Prospero
   • Wolves dispatched in late 30,004, actual razing of Prospero in early 30,005
7. Isstvan III
   • late 30,005
8. Isstvan V
   • mid-30,006
9. Scars released from Chondax
   • early 30,007

Edited July 22 by Tymell

[LSM]

On 7/15/2026 at 5:29 PM, Blissful Brushes said:

... with Istvaan V probably being close to being a lovely Christmas event unless they’re managing to Marshall 7 legions inside a month.

 

While it is outdated lore, the telling in Realm of Chaos: Slaves to Darkness (1988) says: "The crusade against Horus, although of the utmost urgency, took more than 180 days to plan and launch."

 

//

 

In that version:

• General Horus was awarded the title Imperial Warmaster, and was travelling to Terra to accept.
• He fell ill on the feral world of Davin, where (during his convalescence) he was inducted into a local warrior's lodge and possessed by a Daemon.
• Joining in with local traditions was encouraged amongst Imperial soldiery, and Horus' membership was not viewed as unusual.
• A change of character was noted in Horus, and he began to pursue the vision of a new Imperium of Chaos.
• The Warmaster Horus introduced the 'warrior lodges' to the "five Legiones Astartes Chapters under his direct command". [sic]
• This corruption also spread to the Imperial Army and Adeptus Mechanicus [sic] forces under him; undetected by the Inquisition. [sic]
• At Isstvan III, Horus' forces massacre the local populace (which had declared the system an independent principality).
• A group of Loyalist Astartes officers, disapproving of the rot that was spreading through their forces (and those of the Adeptus Mechanicus) seize control of the frigate Eisenstein and flee Isstvan to warn the Imperium. This act is considered the beginning of the First Inter-Legionary War. [sic]
• The Emperor immediately instructed the Inquisition [sic] to purge the Adeptus Mechanicus. All the Titan Legions bar those on Terra declare for Horus, but the priesthoods in control of Collegia supply depots are overwhelmingly Loyal (causing logistical issues for the rebels). 
• The Imperium at large immediately erupts into civil war between Imperial Guard and Imperial Fleet forces; old rivalries re-emerging. 
• Seven entire Marine Chapters [sic] are sent against Horus (taking 180 days to muster), who had consolidated his position at Isstvan V.
• Three complete Chapters took part in the initial assault on Horus, only to find that the four in the follow-up wave had secretly been corrupted. Only five loyal Marines managed to escape the disaster.
• Though Horus had nine rebel Chapters and the Adeptus Mechanicus with him, and three loyal Chapters had already been destroyed, the tide of battle across the galaxy was turning in the Emperor's favour. Horus made a play straight for Terra, in an attempt to "crush the heart".
• In 30 days Horus' forces took control of the Solar System, destroyed the Imperial Fleet's Lunar bases, and laid siege to the Imperial Palace.
• The Imperial Palace was guarded by only the Adeptus Custodes, the few loyalists of the Collegia Titanica, and the Imperial Fists and Whitescar Chapters [sic].
• By the 55th day the Traitor Legions, aided by the machines of the Adeptus Mechanicus, had reached the walls of the Inner Palace.
• With the situation growing desperate, the Emperor disconnected himself from the Astronomican and with an elite cadre of Adeptus Custodes and Imperial Fists teleported directly into Horus command bunker.
• The Emperor kills Horus, but is seriously wounded in turn. He returns to the Imperial Palace, is placed in a life-bubble, and begins overseeing the construction of the Golden Throne (to permanently sustain him).
• With Horus dead, the rebels fall back and leave the system. The Imperial Fleet pursues, hounding them into the Eye of Terror. The Traitors' servants and support troops are given passage to the Eye of Terror on near-derelict hulks; Imperial vengeance tempered by such weakness that no other punishment is possible. 
• With news of Horus' death spreading, fighting is renewed across the Imperium. Loyalists fall upon rebels, as well as all those who attempted to previously remain neutral; while rebels lash out in a final despairing orgy of destruction.
• After seven years the last rebel forces are destroyed or exiled. The Emperor's body breathes its last as he enters the Golden Throne. After less than a decade of fighting, the First Inter-Legionary War - the Horus Heresy - is over.

Edited August 7 by LSM

[librisrouge]

That actually feels like an accurate "in universe" timeline of events. It scrubs the legions, reduces Horus to a general (no traitor primarchs), simplifies the story for the masses, and maintains the importance of the inquisition (which has certainly always existed).

 

It is the sort of thing that 10,000 years of propaganda and mythological/linguisitic drift might create.