Since Warhammer 40,000's 10th edition was released last year, each of the wargame's factions has been getting the traditional rules refresh in the form of a new Codex book. The latest deals with the Adeptus Custodes, genetically engineered bodyguards of the Emperor so gigantic they make space marines look weedy. (They also happen to be Henry Cavill's army of choice). There are 10,000 of them and in the past they've only ever been depicted as men. In this latest iteration, shock horror, at least two of the Custodes are women.
Most players seem to have responded to this by shrugging and getting back to arguing about the new rules, but there's always a vocal minority who go on a tear. The Mail Online ran a typically subtle and understated headline that declared "It's Wokehammer!" and the meme community Grimdank has declared posts about "Femstodes" will only be allowed for one week before they join "Female Space Marine posts" as a banned topic. Games Workshop's official response is a tweet that says, "In regards to female Custodians, there have always been female Custodians, since the first of the Ten Thousand were created."
Is this a retcon? Yep, and it won't be the last. Warhammer 40,000 has had fluid "lore" right from the start. The original Custodian Guards were depicted as shirtless hunks who never leave Earth—a long way from the heavily armored galaxy-spanning golden gods they became—to say nothing of tweaks to the 40K canon like ditching half-eldar space marines and rewriting the Horus Heresy from a short story a handful of pages long into a series of 60+ novels.
The Adeptus Custodes aren't 40K's only genetically engineered supersoldiers, of course. The setting's flagship faction are the space marines, who are created differently—where Custodes are enhanced via a unique process begun when they're infants, space marines begin being grafted with a "gene-seed" when they're on the verge of puberty. And while the explanation that space marine gene-seeds are "keyed to male hormones and tissue types" goes back a way, it's not the real reason Games Workshop made a whole army of dudes who are men.
As GW's former head of IP Alan Merrett once explained on Facebook, "The reason there aren't female Space Marines has nothing to do with lore, or background or character of Marines. It's to do with [the] simple logistics of making miniatures and selling miniatures." In the 1980s GW sold miniatures in sets called blister packs, and as Merrett explained "the intention was that upwards of 25% of all models would be female." That didn't last because "retailers kept complaining to us that customers weren't buying the female models and could we not include any in their restocks." By the time Warhammer 40,000 was designed, GW made sure its poster boys were, well, boys to ensure they'd sell. As Merrett put it, "All the background fluff about why there are only male Marines is there to justify a commercial logistics issue."
And the same was true of the Adeptus Custodes, until it wasn't. Though the customers at the average Warhammer shop are mostly men, these days there are usually one or two women as well. And the men are a lot less likely to throw a hissy-fit about having women in their armies than gamers in the 1980s, despite what Reddit and Twitter might suggest. All of 40K's lore and storytelling exists to provide context for selling toy soldiers to people, and as the customer base changes so too will that lore.