Why didn't the Chieftains of the Dúnedain before Aragorn II claim the throne of Gondor?

Thomas Snerdley's answer to The Lord of the Rings (books, movies and creative franchise): Why didn't the Chieftains of the Dúnedain before Aragorn II claim the throne of Gondor? - Quora

"The claiming of the reunited throne of Arnor and Gondor was driven by the geopolitical realities of Middle Earth rather than whether the shards of Narsil were reforged into Andúril. Military victory over Sauron was a necessary precursor to political reunification.

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The heirs of Isildur (Chieftains of the Dúnedain) before Aragorn II could not hope to reunite the North and South Kingdoms for several reasons:

1) The existential threat to Gondor posed by the lord of Mordor.

2) The non-existential but significant threats facing the former territories of Arnor -- and in particular the Chieftains of the Dúnedain -- due to the depredations of the orcs of the Misty Mountains and other vassals, minions and spies of Sauron.

3) The growing threat posed to Rohan and eastern Enedwaith (which separated the North and South Kingdoms) posed by Saruman's machinations against King Théoden.

In the decades before the War of the Ring, the Chieftains of the Dúnedain lacked the capability to nullify any of these threats. In fact, both Rohan and Gondor were severely challenged merely attempting to repel encroachments against their borders and peoples. At this time, the public pronouncement of the existence of a legitimate Heir of Isildur would merely have resulted in Sauron launching waves of assassins against him. Numerous Chieftains of the Dúnedain had been slain by either orcs or wolves/wargs upon discovery by Sauron's agents (including Arathorn I, Arador and Arathorn II).

Happily, during the Chieftainship of Aragorn II all of the necessary ingredients came together enabling him to terminate Sauron's existential threat to Gondor as well as relieving incidental threats against Rohan and Rhudaur (eastern Arnor). By far the most important aspect of this was the discovery of Sauron's Ruling Ring which offered the only viable prospect of completely destroying Sauron. Other ingredients included:

1) the White Council driving Sauron from Dol Guldur (relieving pressure against Lothlórien and northeastern Rohan

2) the death of the dragon Smaug which removed a massive potential threat to eastern Arnor or Gondor

3) the tripartite union between the elves of Mirkwood, the men of Dale and the dwarves of Erebor

4) knowledge of the Paths of the Dead and the potential utility of the Dead men of the White Mountains

With these geopolitical elements in place ... and with a tremendous dollop of luck and heroic actions by all the members of the Fellowship of the Ring, Lady Galadriel and warriors of both Rohan and Gondor ... it was possible to remove the threat of Sauron from Middle Earth. In the event, Narsil/Andúril played a relatively minor role.

Only with Sauron dispatched, Saruman de-fanged and both of their armies dispersed could the North and South Kingdoms be reunited and the Heir of Isildur claim the throne without being swiftly assassinated."


Me: Why not long before Sauron's return, though?

Before he declared himself in Mordor he wasn't quite as powerful. During the Watchful Peace, for example.

Him: 1) By the time of the Watchful Peace (years 2063 - 2,460 of the Third Age) the Kingdom of Arnor hadn't existed for over 1,200 years. When Eärendur, the tenth and last King of Arnor, died in the year 861 of the Third Age, his three sons split up the kingdom into three separate provinces, Arthedain, Rhudaur and Cardolan.

2) The kings of the three divided provinces squabbled amongst each other for power and were bled white by over six centuries of conflict with the Witch King of Angmar from around the year 1,300 to 1,965 of the Third Age.

3) The Dúnedain kings in Rhudaur had already been ousted from leadership, and possibly all slain, by hill-men who allied themselves with the Witch King.

4) In 1409 of the Third Age, the Witch King's forces overwhelmed the province of Cardolan and slew its last Dúnedain king.

5) The remaining Dúnedain of Arthedain were grievously weakened when the Witch King of Angmar overran Arthedain and King Arvedui drowned in the Bay of Forochel. In fact, they would have been annihilated and gone extinct had not King Eärnil II and Glorfindel of the House of Elrond arrived together at the head of powerful armies to defeat the Witch King.

6) Following this, the Dúnedain of Arthedain struggled merely to keep their lineage unbroken and to avoid discovery and assassination. In the period of the Watchful Peace, Aragorn I was slain by wolves (possibly evil Wargs of the Misty Mountains). Far from entertaining ideas about expanding their claims, they merely limped along hoping not to be exterminated.

7) Any Chieftain of the Dúnedain in Arthedain with delusions of grandeur would still be painfully aware of King Arvedui's attempt to assert his rightful claim to the kingship of Gondor, which was rebuffed in favor of King Eärnil II.

8) During the years of the Watchful Peace the Stewards of Gondor had relaxed their vigilance against Sauron since he seemed to be quiescent. The formerly powerful border defenses in the east and west (including the Tower of Orthanc) were abandoned or allowed to crumble. The Stewards' attention was devoted to internal reconstitution rather than external expansion.

In short, the only realistic scenario for reunion of the North and South Kingdoms was to destroy Sauron, revitalize Gondor and use that legitimacy to reassert control over the fractured northern areas that had once comprised the Kingdom of Arnor. Because of the disappearance of Sauron's Ruling Ring, this simply wasn't possible during the years of the Watchful Peace.