Here is an excerpt:
Rhudaur is always portrayed as an evil land. Its people betrayed the Dunedain and killed them or drove them out. The Hobbits who settled there fled. Trolls ventured down from the hills and drove everyone away. But when Elendil sailed to Middle-earth and established the Kingdom of Arnor, the Dunedain who settled in Rhudaur must have been members of his own following. They were Faithful Númenoreans who venerated the Valar and lived in friendship with the Eldar of Aman and Middle-earth. These were not evil people. So what happened?
Well, in one sense, progress may have happened. That is, the character of the people and their culture must have changed progressively through the centuries. And there were probably several reasons for the change, reflected in different periods and events in Rhudaurian history.
The region claimed by the Kings of Rhudaur in the middle Third Age extended eastward from the Weather Hills to the Misty Mountains, and south from the Mitheithel (Hoarwell) where it flowed past the Ettenmoors to the tip of the Angle, the land between the Mitheithel and Bruinen (Loudwater) rivers. The rivers joined together above Eregion and became the Gwathlo (Greyflood), the chief cities of which were Tharbad and Lond Daer Ened (formerly Vinyalonde).
When Elendil arrived at Lindon with four ships of Faithful Numenoreans, Eriador was already well-populated by Elves, men of Edainic descent, Numenoreans, men of mixed heritage, and men who are probably best described as “Easterlings”. These Easterlings must have dwelt in the foot-hills of the Misty Mountains, mostly north of Imladris (Rivendell). There may have been some clans which lived in the lowlands east of the North Downs and the Weather Hills.
The Numenorean peoples must have accepted Elendil as their lord almost immediately. Faithful Numenoreans had been leaving Numenor for years, and most of them came from Andunie, the province of Numenor where Elendil’s father had been Lord, until he was removed by Ar-Pharazon. The salvation of a beloved noble family should have encouraged the Numenoreans of Eriador to retain their traditions.
In “Of the Rings of Power and the Third Age”, J.R.R. Tolkien writes that Elendil’s “people dwelt in many places in Eriador about the courses of the Lhun and the Baranduin; but his chief city was at Annuminas beside the water of Lake Nenuial.” Yet other places of Numenorean settlement included “Fornost upon the North Downs” and “in Cardolan, and in the hills of Rhudaur.”
We also know, from other writings, about the city of Tharbad. Lond Daer Ened may have been destroyed in the floods which ravaged the coastlands of Middle-earth after Numenor was destroyed and the world was changed. Or it may be that Lond Daer Ened became deserted sometime early in the Third Age, much as Annuminas did. But the principal inference we may draw from these references to Elendil’s people is that the majority of them dwelt in western Eriador.
So what made Rhudaur so important that Elendil sent people to colonize the region? Furthermore, why were the Dunedain never able to fully integrate with the local population?
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