I saw this years ago and I still think it was primitive office humor. Snails ate delicious plants and there were probably monks waging a war against them. The incredulity of fighting so hard against an enemy so weak was funny.
Because they probably had a great sense of humour, comedy clubs and memes back then too, but hey let's ignore that for just a moment to imagine how hardcore a knight you would have to be to fight off Cthulhu snails
Humanity was ruled by giant snails and their hyper intelligent queen, and it was only through the bravery of these fine knights were our shackles cast off and the mollusk menace thrown down.
And, in great effort to hide our collective shame, all knowledge about this was intentionally purged, Save for a few manuscripts who managed to be overlooked or were kept in hiding, so hints of humanities true history would be known.
"And if you join our ranks today, they never will!"
-Me, while extending my hand out in invitation for YOU READING THIS to join the...
Associated
Society of
Snail
Hunters and
Ancient
Truth
Seekers
...yes, I know. Yes, we're technically the "A.S.S.H.A.T.S."...
Yes very funny, okay, have your moment... It's a secret society okay, so it doesn't actually even come up, nobody will know, it's fine.... IT'S FINE.
I mean, I would guess dragons were a thing because of dinosaur skulls being found a long time ago. There were also giant dinosaur mollusk shells, so maybe this is the equivalent?