Os Barrowdowns eram os restos do reino de Cardolan. A história de sua queda e o habitar dos carrinhos de mão estão no Apêndice A:
Rhudaur era apenas um estado vassalo de Angmar, então é um cânon que os espíritos malignos definitivamente vieram do Reino das Bruxas de Angmar. O despertar foi, com efeito, feito por esses espíritos malignos - eles eram a sombra de longe, e mexeram (controlaram) os ossos que já estavam nos montes. Não é explicado se eles foram enviados especificamente pelo Rei Bruxo ou se foram por sua própria vontade, mas eu acho que é uma suposição razoável que o Rei Bruxo teria estado envolvido, especialmente neste momento e dado o benefício estratégico de efetivamente impedindo qualquer acordo adicional de um dos Reinos dos Dunedain.A great host came out of Angmar in 1409, and crossing the river entered Cardolan and surrounded Weathertop. The Dúnedain were defeated and Arveleg was slain. The Tower of Amon Sûl was burned and razed; but the palantír was saved and carried back in retreat to Fornost, Rhudaur was occupied by evil Men subject to Angmar, and the Dúnedain that remained there were slain or fled west Cardolan was ravaged. Araphor son of Arveleg was not yet full-grown, but he was valiant, and with aid from Círdan he repelled the enemy from Fornost and the North Downs. A remnant of the faithful among the Dúnedain of Cardolan also held out in Tyrn Gorthad (the Barrowdowns), or took refuge in the Forest behind.
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In the days of Argeleb II [1670-1743] the plague came into Eriador from the Southeast, and most of the people of Cardolan perished, especially in Minhiriath. The Hobbits and all other peoples suffered greatly, but the plague lessened as it passed northwards, and the northern parts of Arthedain were little affected. It was at this time that an end came of the Dúnedain of Cardolan, and evil spirits out of Angmar and Rhudaur entered into the deserted mounds and dwelt there.