Folklore of Discworld by Terry Pratchett Page A

people think, but their brains function properly only at low temperatures (because of the silicon), so the warm climate of the valleys and plains makes them very sluggish, especially in the daytime. Detritus now gets some help from a small fan attached to his helmet, but it was only when he was accidentally shut in the refrigerated Pork Futures Warehouse that his true intelligence was revealed – as he gradually froze, he scratched calculations worthy of Einstein all over the iced-up walls. There are hints that trolls have age-old cultural traditions which no outsider knows anything about; there is talk of their history chants and stone music, for instance, and of their Long Dance. They think of Time in a curious though logical way: the future, they say, must be behind you, since you can’t see it, but the past, which you can see in your memory, must be ahead.
    There is an age-old feud between trolls and dwarfs, possibly arising from the fact that both races live in the same mountain regions, and that dwarfs spend their lives mining and tunnelling through rock – something which trolls find it upsetting to think about. It is even rumoured that dwarfs have occasionally tunnelled into the underside of a particularly stony and immobile troll. Be that as it may, the feudled to the disastrous battle of Koom Valley, said to be the only occasion in military history where each army ambushed the other. It was long ago and far away, but has never been forgotten. Koom Valley has become a myth, a state of mind.
    Where any dwarf fought any troll, there was Koom Valley. Even if it was a punch-up in a pub, it was Koom Valley. It was part of the mythology of both races, a rallying cry, the ancestral reason why you couldn’t trust those short, bearded / big, rocky bastards. [ Thud! ]
    And yet … and yet … if other myths can be trusted, the first man, the first dwarf and the first troll all originated in a single egg of stone, a geode, more than 500,000 years ago, and are therefore, in some sense, brothers. This myth was mentioned above, in the section on dwarfs. Its implications, together with the story of what really happened in Koom Valley, are explored in Thud!.
    Trolls also have a dislike of druids, who can be found in the small, rainy, mountainous kingdom of Llamedos. There is no mystery about the reason, for the druids of the Disc went around erecting huge stone circles in much the same way as (some folk used to say) British druids did at Stonehenge. Regrettable errors occurred:
    Any sapient species which spends a lot of time in a stationary, rock-like pose objects to any other species which drags it sixty miles on rollers and buries it up to its knees in a circle. It tends to feel it has cause for disgruntlement. [ Soul Music ]
    Even the dragging on rollers is not the worst of it. It is said (as recorded in The Light Fantastic ) that one particularly skilled group of druids found a way to quarry huge slabs of high-quality stone and fly them hundreds of miles along ley-lines to the snowy Vortex Plain, where they set them up as an immense construction of concentric circles, towering trilithons, and mystic avenues, to be a greatcomputer of the skies. It proved hopelessly inaccurate. This act of wanton cruelty to minerals made trolls still more bitter towards druids.
    On Earth, there are two quite different races claiming the name ‘troll’. One lot is to be found in Denmark: these are smallish mischievous goblins with red hair, living inside mounds and hillocks near farmland. They can be disregarded here since, apart from the name, they have nothing in common with Discworld trolls, and seem akin to Feegles.
    The other ones, however – the huge mountain trolls who live in Iceland and Norway – are remarkably like those of the Discworld, but wilder and more hostile to human beings. They are thought to be the direct descendants of the dangerous Giants of Scandinavian myth, but differ from them in being generally solitary creatures.