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Warhammer 40K: Six Of The Grimdark’s Biggest Retcons

6 Minute Read
Aug 4 2022

Let’s talk about a few times 40K underwent some major retcons.

Warhammer 40,000 has a long history. This is true both in-game and in real life. It’s a setting filled with a thousand storylines full of mystery and contradiction. Over the long years 40K has undergone a few, just a few, retcons. These changed what we had been told was true (or as true as anything in the Grimdark is) to something altogether new. Today let us take a look at a few major changes that for better or worse reshaped the setting.

6. The Squats Are Dead

The Squats were a major army in the dawn times of 40K. For a couple of editions they battled across the tabletop. Then… they vanished. It was never really officially stated what happened. However, the generally accepted view was that they had been wiped out. It was also possible they had never existed. That was until this year. Then GW decided to bring them back. With some major retcons on their history and lore. Good times!

5. The Origins of the Deathwatch

Originally it was stated that the Deathwatch were formed during the Apocryphon Conclave of Orphite IV. This was a grand conclave of the Ordo Xenos. At it, the Inquisition debated how best to deal with the rising threats to the Imperium, in particular the many Xenos races. Ultimately the Inquisition met with a large gathering of Chapter Masters. They agreed that a dedicated force of anti-Xenos veterans would work best. Thus was born the Deathwatch.

Sometime later however Black Library went back and retconned this origin.  Under the new story, the Deathwatch was formed during the War of the Beast. During this conflict, the Imperial Fist’s Chapter Master and Lord Commander of the Imperium realized that he needed small dedicated strike teams of veterans to help win the war. The original squads were formed out of survivors from other conflicts in the war. After their usefulness was proved, they gained a permanent role in the Imperium.


4.  X- Was Here All Along

This is kind of a catch-all category and comes up a lot. Prior to 8th Edition and the Great Rift, there wasn’t a lot of technical innovation among the races of 40K. This was especially true when it comes to the Imperium. Thus when the game designers wanted to add something new to the game they often will simply go back and retcon things so that of course that thing was here all along. Heck, it’s been used for thousands of years.  You, uh, you just never saw it. Space Marines are the most visible targets of this. However, other factions such as the Astra Militarium have gotten the treatment. Arguably the Adeptus Custodes have been the most affected by these changes. They had an entire army worth of variety retconned into existence.

3. Why the Alpha Legion Turned

You could maybe argue that this wasn’t a retcon at all. Early on I’m not sure we ever had a clear reason why the Alpha Legion turned traitor. Still, it was readily assumed, and hinted at, that the Alpha Legion like the other fallen Legions had been slowly corrupted by the forces of Chaos. Ultimately they joined Horus when he called them to his side. However, the novel Legion retconned things. It made the Alpha Legion secretly loyal. It was revealed that they had turned traitor at the behest of an Xenos Cabal. This was in order to ultimately thwart the plans of Chaos. It was also revealed/retconned that the Alpha Legion had not one but two Primarchs, identical twins hidden from all.

2. Eldar/Human Ultramarines

Look, early 40K was weird (at least compared to what we’ve come to know) and a lot of things that were true back in Rogue Trader have slowly been retconned away. Now a certain number of those retcons fall under the “well you didn’t know the whole story” or “this was there all along” category, or even the “might be true” or “just some random propaganda”. One of the oddest things though was the Imperium’s view towards Xenos at the time. Suffering not the Xenos to live is such a cornerstone of 40K that it has become its own meme and the Imperium’s opposition to Xenos is legendary (see the first entry on this list). And yet it wasn’t always so.

Back in the day the Imperium was pretty welcoming of the Xenos, Illiyan Nastase up there was the Chief Librarian Astropath of the frigging Ultramarines was a known half human/half Eldar mix. Note that he was also an important player in Terra’s politics. Another idea retconned away we can see with him, is that Librarians, or other people, might serve with various Chapters for a period of time.


1. The Black Crusades Weren’t Failures…

This might be the biggest retcon of all time. Over the many years of the Long War, Abaddon the Despoiler, Warmaster of Chaos has repeatedly tried to bring down the Imperium. Though he had led many attacks against the forces of the Corpse God, the greatest of his campaigns were known as the Black Crusades of which he launched 13. Each of these posed a major threat to Imperial Space, yet ultimately each time the Imperium rallied together and at great cost thwarted the Despoiler, sending him screaming back to the Eye of Terror vowing to return like a Saturday morning cartoon villain. The final, the 13th, Black Crusade was a massive assault against the fortress world of Cadia, covered in the Eye of Terror campaign in 2003, this campaign also saw Abaddon defeated and thrown back. For 14 years he waited in the Eye of Terror plotting anew.

…But All Part Of The Plan!

Then in 2017 came the big retcon. The 13th Black Crusade was never defeated it turns out. The victory won in the Eye of Terror campaign, which seemed final, was actually just won against perhaps the vanguard and the real attack hadn’t even happened. Indeed everything was going just as planned for Abaddon. Even more “surprising” all his other failed Black Crusades weren’t failures at all, they had all been targeted strikes that had succeeded in achieving the Despoiler’s esoteric goals. Abaddon wasn’t the biggest failure or pasty in the galaxy, but actually the greatest mastermind of all time.

With the destruction of Cadia, a series of defeats turned into a victorious road map to dealing the Imperium the greatest blow it had felt since the Heresy. Abaddon was redeemed. Of course this new Abaddon surely wouldn’t just go back to his old habits of half victories and losing to Imperials right away would he? Whats that? Whats a Vigilus? Never heard of it.

Let us know what you think was the biggest retcon in 40K, down in the comments! 


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