You can find information about Arnor and its peoples in THE LORD OF THE RINGS, UNFINISHED TALES, THE PEOPLES OF MIDDLE-EARTH, and a couple of other books. It's mostly little bits and pieces scattered everywhere. One of the main reasons why I'm writing a history book for Middle-earth is that so many people, like you, want to know what exactly Tolkien wrote (and even I cannot guarantee the most thorough answers to such questions) about these lands and peoples.

: Also, the division never seemed very fair. Arthedain got to
: have the old capital of Annuminas and the new capital of
: Fornost, as well as all three of the Palantir. It also got
: what became the Shire, Bree, Amon Sul (At least I assume so)
:. . .Cardolan got. . . hmm, the coast, Tharbad, the South and
: Barrow Downs? That doesn't seem too good. And Rhudaur seems
: to have gotten completely screwed. What population centers
: would there have been in Rhudaur? The Angle?

We have to resort to speculation to figure out the significance of the divisions, so each person will come up with something different. I'm not really sure of who got Amon Sul. In some places Tolkien says Cardolan and Rhudaur fought over it, and in other places he indicates that Arthedain controlled it.

Were there any towns in Rhudaur? I don't know. At least three peoples settled there: the hill-tribes, the Dunedain, and the Hobbits (who came much later). Whether anyone else lived there (besides possibly some Elves), I don't know.

: Also, were there any regional lordships in Arnor like those in
: Gondor (whether they're feudal or not I leave to others)?
: Also, who were the "Evil Hill Men" who lived in Angmar and took
: over Rhudaur?

I think Rhudaur and Cardolan were probably regional lordships to begin with. But that is just a guess.

: Besides the Dunedain, who lived in Arnor? Dunlending related
: people seem to have spread up through Cardolan to Bree, but
: what other peoples are living in Arthedain and Rhudaur? (Evil
: Hill Men? Other Edain related types?? Someone else???)

: Well, I guess that's all.

That's quite a bit. :)

Peoples whom I know lived in Eriador during the Second Age include:

1) Edain (mostly Bëorians, some Marachians)
2) Gwathuirim (technically related to the Edain through
their kinship with the Folk of Haleth)
3) A people whom I'll call "Borians"...see below
4) Some of Morgoth's Easterlings, apparently the ancestors of
the Men of Angmar in the Third Age (and probably also the
hill-tribes)
5) Nandorin Elves
6) Sindarin Elves
7) Noldorin Elves
8) Possibly Avarin Elves (maybe even of more than one tribe)
9) Numenoreans (Elf-Friends)
10) Men of mixed ancestry

The Folk of Bor were completely destroyed in the First Age. They were clans of farmers who migrated north around the Ered Luin and who settled in Lothlann north of the March of Maedhros. They remained faithful to the Noldor but were massacred by the Folk of Ulfang in the Nirnaeth Arnoediad (and/or other Easterlings who came later).

In THE WAR OF THE JEWELS there is a footnote in the Grey Annals which states "Of the people of Bor, it is said, came the most ancient of the Men that dwelt in the north of Eriador afterwards in the Second Age." These Men were not desceneded from the tribe known as the Folk of Bor, but rather from related clans which did not answer Morgoth's call.

Where did they live? Probably close to the Lhun between the Emyn Uial and the river, about parallel with the Dwarven lands. This would have been north of the Elvish territory. I do not know if they eventually gave rise to the Lossoth of the Third Age.

The Forodwaith named on the LOTR map refers to an ancient people (the Northern People) who lived north of eastern Eriador beyond the mountains. Tolkien tells us virtually nothing of them (by that name) but I have guessed they were originally Easterlings who served Morgoth in the First Age and fled after the War of Wrath. From them may have come the Men of Angmar and the Hill-men of Rhudaur.

The Edain who stayed in Eriador or returned there during the Wars of Beleriand (most notably around the time of the Dagor Bragollach, when Estolad was abandoned) seem to have lived mostly in Tyrn Gorthad, the North Downs, and the South Downs. These were primarily Bëorians, a semi-woodland folk (in Beleriand, at least) who pastured flocks of sheep in the hills. Only a few Marachians seem to have lived in Eriador.

Twelve chieftains were selected to meet with Vëantur the Numenorean in S.A. 600 but Tolkien gives no indication of how many tribes or clans they represented. Nor does he indicate whether any of them were descended of Bereg, the grandson of Bëor who led a thousand of his people south out of Beleriand (they would have come out around the lands that later became western Gondor, but they could have migrated north from there).

The lands of Minhiriath (between the rivers Baranduin and Gwathlo) were largely forested and the home of Gwathuirim (who also lived on the south side of the Gwathlo). These men were not necessarily unfriendly to anyone, but they were awed by the Elves and apparently feared them, unlike the Folk of Haleth.

From about S.A. 1200 on the Numenoreans began to make permanent havens in Middle-earth. Tolkien doesn't tell us where the first havens were but it may be that Aldarion's old seasonal haven of Vinyalonde was made into a permanent settlement during these early years. On the other hand, it was most renowned as Lond Daer Ened, the Great Middle Haven (between Pelargir and Mithlond), so it may not have been fully established until after Pelargir was founded.

As the Numenoreans became more ensconced in Middle-earth they began to mingle with the local peoples, but whatever populations may have existed in Eriador at the time of the War of the Elves and Sauron seem to have been displaced or destroyed. I would guess that the Forodwaith did not begin to migrate south until after the war, and that the Edain probably were confinded to the central hill-lands. The Bree-men may have established themselves soon after the war since the great forests were destroyed and the Gwathuirim had to flee to Eryn Vorn (a forest on the northern coast of Minhiriath just below the Ethir Baranduin) or to the western dales of the Misty Mountains (this latter group became the Dunlendings, who appear to have become sub-divided into two groups in the Third Age, "wild hill-men" and shepherds of the lowlands).

As the Numenoreans spread throughout Eriador they must have mingled with the Edainic peoples living there, perhaps even including some of the Gwathuirim. So, by the time Elendil founded Arnor he could have potentially ruled people of Numenorean descent who had grown up in Middle-earth, his own exiled Numenoreans, people of mixed Numenorean/Edainic heritage, Edain, Gwathuirim, and possibly some Borians and Forodwaith.

The latter could have remained outside of Elendil's realm and become a part of Arnor only in the Third Age.

Tolkien says that Elendil's people lived in Emyn Uial, the North Downs, the South Downs, Tyrn Gorthad, and along the banks of the Baranduin. They also lived at Tharbad, which was a Numenorean haven and fortress. Arnor and Gondor both kept garrisons there for many centuries.

Only three cities are actually named: Annuminas, Fornost Erain, and Tharbad. I suspect Lond Daer Ened was either abandoned by the time of the Downfall of Numenor or else destroyed by the great floods which ravaged the coastlands of Middle-earth.

Bree probably became important around this time and must have been considerably larger than at the end of the Third Age. I don't know if we should guess it was a city, however.

I find it hard to believe there were no other towns in Eriador during Elendil's reign. Rather, I think that all such towns had disappeared by the end of the Third Age and thus their names were lost to time. Tharbad was still remembered because it had been abandoned only a century before the War of the Ring.

If I had to guess where towns might have existed, I would put one at the Ethir Baranduin, one at Sarn Ford, one in Tyrn Gorthad, one in the South Downs (if not more than one), and at least one other town in the North Downs (further away from Fornost Erain).

I don't think it would be unreasonable to postulate towns between the Baranduin and the White Downs, either, especially at the Bridge of Stonebows, where the Great Road crossed the Baranduin.

Presumably there would have been innumerable villages scattered throughout Eriador, probably mostly situated alongside small streams and rivers (much like many of the towns and villages of the Shire are). And there would have been farms, freesteads, and possibly great estates scattered across the lands as well.

Although Tolkien doesn't speak of any wars prior to the rise of Angmar, I suspect that in the Third Age Arnor's kings fought one or more wars with the Forodwaith. These northern people may have increased in number and begun migrating south. At least one Arnoian king did die prematurely. He may have fallen in battle with these migrating clans.

When Arnor was divided between the sons of Earendur, the division may have resulted from a civil war. Let us suppose that one of the brothers had popular support in the south. The clans of Minhiriath and the Dunedain of Tyrn Gorthad and the South Downs supported him for some reason. The other brother, perhaps the youngest, may have raised support among the Hill-tribes as well as the easternmost Dunedain (who seem to have always been few). By this time we should presume the Hill-tribes were distinct from the more northerly clans of the Forodwaith (and it is not unreasonable to presume the Hill-men were simply descended from a completely different group of Easterlings -- they could even have migrated to the region during or after the War of the Elves and Sauron, when the Edainic civilization in Wilderland was destroyed).

Could there have been a division of Arnor's army? I don't know. Why would Dunadan soldiers rebel against their rightful king? Maybe there was no civil war. The mere threat of a war might have been sufficient to convince Amlaith of Fornost to let his brothers secede with part of the realm. But lately I've become convinced there must have been a war, perhaps even a rather bitter one, though not as devastating as Gondor's kin-strife.

I think the Hill-men were important to Rhudaur's kings. Tolkien seems to imply that there were simply too few Dunedain in the east to hold the land.

There were probably no more than six kings of either Rhudaur or Cardolan, and probably only five. Amlaith was the eldest son of Earendur, so his brothers may have outlived him (unless in their state of rebellion their lives were shortened -- that's a sticky issue). The original entries for the Kings of Arthedain indicate that it was Malvegil, not his son Argeleb I, who attempted to reassert the elder line's authority over Rhudaur and Angmar. So I don't believe there were any descendants of Isildur left in either Rhudaur or Cardolan by, say, 1300.

That would allow about five generations of kings in both countries. Although I cannot speculate on what happened in Cardolan, I would guess that the Line of Isildur met with a violent end in Rhudaur.

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Parma Endorion: Essays on Middle-earth, Revised Edition