Trolls and the Olog-hai

Question

In The Hobbit, Tolkien presents three trolls (Bert, Tom, and Bill Huggins) who are decidedly comic figures:

They were trolls. Obviously trolls. Even Bilbo, in spite of his sheltered life, could see that: from the great heavy faces of them, and their size, and the shape of their legs, not to mention their language, which was not drawing-room fashion at all, at all. ...

Yes, I am afraid trolls do behave like that, even those with only one head each.

Then in Chapter 2 of The Fellowship of the Ring, "The Shadow of the Past", we are told:

Trolls were abroad, no longer dull-witted, but cunning ...

And indeed the once or twice that we see trolls (once in the Chamber of Mazarbul—and again near the bridge of Khazad-dûm; and once near the end of the War of the Ring, in the Battle of the Morannon—or is that the name?), they are fearsome opponents, though perhaps we don't see them long enough to decide that they are indeed "cunning".

Is there any description in Tolkien's letters or in the History of Middle Earth of how The Hobbit's trolls became The Lord of the Ring's Olog-hai?

I'd accept an in-universe or out-of-universe answer; that is, either a description of what Sauron did to effect such a change, or a description of how Tolkien changed (or perhaps did not change) his description of the encounters with trolls in either of the books.

Answer 1

In-universe

The trolls we see in The Hobbit (and whose corpses we see briefly in LOTR) are the descendants of stone trolls, far removed from their homelands and who seem to have been corrupted by easy-living and the availability of fresh food like mutton and the occasional hobbit. Their speech has become more refined than that of a normal troll. They even seem to have become a byword for slow-witted brutishness in Shireish society.

At the start of LOTR we learn that the Dark Lord has started on a schedule of improvements to their species. He's engaged in a comprehensive breeding programme (ultimately leading to the creation of the Olog-Hai) and appears to be using a mixture of education and dark magic to make them more vicious, stronger, larger, more cruel and resistant to sunlight. In short, Sauron is...

"teaching them what little they could learn, and increasing their wits with wickedness." _{^{LotR. app.F.}}

Out of Universe

It's very important to note that 'The Hobbit' was written as a children's novel. The characters are broadly drawn, often verging on caricature. Although Tolkien's children especially liked the rustic and farcical trolls, when it came time to write the Lord of the Ring books, he seems to have regretted his decision to make them quite so...human.

In a 1954 letter to Peter Hastings, an Oxford bookshop manager. He observed that:

“I do not know about Trolls. I think they are mere 'counterfeits', and hence...they return to mere stone images when not in the dark. But there are other sorts of Trolls beside these rather ridiculous, if brutal, Stone-trolls, for which other origins are suggested”

Tolkien retconned the trolls by ditching the old trolls and replacing them with...

“a troll-race not before seen appeared in southern Mirkwood and in the mountain borders of Mordor. Olog-hai they were called in the Black Speech. That Sauron bred them none doubted, though from what stock was not known.” We are told that “the Olog-hai were in fashion of body and mind quite unlike even the largest of Orc-kind, whom they far surpassed in size and power. Trolls they were, but filled with the evil will of their master: a fell race, strong, agile, fierce and cunning, but harder than stone. _{^{LotR - RotK}}

This allowed him to keep the narrative of the Hobbit intact (even throwing in a scene where the Fellowship come across the three rustic trolls) and yet present more older readers with a more realistic and threatening aspect.

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For a much more detailed analysis on this subject, I'd strongly suggest a read of the essay; "The Many Faces of Trolls in Middle-earth" by Andrew C. Peterson

Answer 2

It's wrong to think of a direct line of improvement from the Trolls of the Hobbit to the Trolls of LotR; in fact the Trolls as presented in the Hobbit were actually a reversion-to-primitive when compared to Trolls presented elsewhere in Tolkien; for example at the Battle of Unnumbered Tears:

Last of all Húrin stood alone. Then he cast aside his shield, and wielded an axe two-handed; and it is sung that the axe smoked in the black blood of the troll-guard of Gothmog until it withered, and each time that he slew Húrin cried: "Aur�� entuluva! Day shall come again!"

What's particularly notable is that this scene (from Silmarillion chapter 20) took place in daylight (the text mentions the sun going down just after this scene), so these Trolls from the First Age aren't turned to stone either, and nor is their fighting ability impaired by daylight. Clearly a superior breed, indeed.

History of Middle-earth 12 (The Peoples of Middle-earth) has this to say about Trolls, in material that was originally written for the Appendices but cut for reasons of space:

Trolls, in their beginning creatures of lumpish and brutal nature, had nothing that could be called true language of their own; but the evil Power had at various times made use of them, teaching them what little they could learn, and even crossing their breed with that of the larger Orcs. Trolls thus took such language as they could from the Orcs, and in the west-lands the Trolls of the hills and mountains spoke a debased form of the Common Westron speech.

Altogether it seems clear that there were in fact many different sub-species of Troll, and that those we meet in the Hobbit were just from a different (and perhaps more primitive or degenerate) sub-species to those of the Silmarillion and Lord of the Rings. Based on that, there seems no need to require any kind of development from one type to another.