[Arathul]

The keeping of the line of Isildur pure and unbroken allowed King Elessar to reunite the thrones of Arnor and Gondor in T.A. 3019. However, my opinion for this is that the fall of Arnor was directly related to the Northern Numenorean’s refusal to intermarry and intermingle with indigenous Men of Middle-earth.

To make a case for this idea, I need to show that:
A) The Northern Line of Isildur did not intermarry with non-Numenoreans.
B) The Southern Line of Anarion did intermarry with non-Numenoreans.
C) The intermingling saved Gondor
D) The lack of intermingling caused the fall of Arnor.

The Northern Line did not intermarry
This is fairly straightforward and easy to confirm. Aragorn, the last of the purely Northern Line, is described as “the thirty-ninth Heir of Isildur in the direct line.”(1) Gandalf(2) and Elrond(3) confirm this as well. “It was the pride and wonder of the Northern Line that, though their power departed and their people dwindled, through all the many generations the succession was unbroken from father to son.”(4) If there still is any doubt of the lineage of the women these sons married, they are laid to rest with an account of the parents of King Elessar. His father Arathorn was directly descended from Isildur, of course, and his mother was Gilraen the Fair, daughter of Dirhael, who was descended from Aranarth, the First Chieftan, who was himself descended from Isildur.(5) The only trace of non-Numenorean blood that can be traced would be Arvedui’s wife Firiel, who was the daughter of King Ondoher of Gondor. Ondoher traced his lineage back to King Eldacar, who was half Rhonovianian.(6)

The Southern Line did intermarry
This is also easy to confirm. A great deal of information is given regarding Valacar’s marriage to Vidumavi, princess of Rhovanion. Their son, Eldacar (Vinitharya), came to the throne of Gondor and survived the Kinstrife. Yet other Numenoreans in Gondor had previously intermarried: “For the high men of Gondor already looked askance at the northmen among them; and it was a thing unheard of before that the heir to the crown, or any son of the King, should wed one of lesser and alien race.”(7) More explicitly, “after the return of Eldacar the blood of the kingly house and other houses of the Dunedain became more mingled with that of lesser Men.”(8)

The intermingling saved Gondor
This is the first of my ideas that may need some hard proofs to convince. To begin with, we know that war never ceased on their borders.(9) Gondor was mostly victorious, although their power waxed in the eleventh century. By the thirteenth, when the Kinstrife erupted over Eldacar, Gondor had faced two centuries of slow decline. Gondor never fully recovered from the Kinstrife. Many of the Dunedain were slain, and some fled to Umbar and Harad because they refused to acknowledge Eldacar. There were many Numenoreans killed or departed, and the records clearly state that “the people of Gondor were replenished by great numbers that came from Rhovanion.”(10)

Gondor clearly needed replenishing, because in the years that followed great evils rapidly followed upon the heels of one another. Plague, wars with Umbar, and the invasions of the Wainriders beset Gondor from the fifteenth to the nineteenth centuries. Things reached a low point in the twentieth, when the general Earnil of the Southern Army alone saved Gondor from being overwhelmed from the East and South.

Throughout this long time period the descendents of the Kings had become few. Some were killed in the ceaseless wars, some did not marry, some fled to Umbar out of fear, and some “renounced their lineage and taken wives not of Numenorean blood.”(11)

This intermingling had two effects. First, it ended up destroying the Southern Line. No claimant of pure blood could be found. Second, it saved the nation of Gondor. I have already quoted the “replenishment” statement. Gondor needed immigration and new blood to survive the constant threats and attacks. Immigration came from the North, as we know, but there was also intermingling that had gone on in Lamedon and other provinces of Gondor that were on the southern edge of the White Mountains.(12) Without this help and intermingling, there was little chance that the Exiles could have survived.

The lack of intermingling caused the fall of Arnor
The Numenoreans in the North had always been in lesser number than in the South. Before the Drowning, the colonies of the Faithful were at Tharbad in the North and at Pelargir and the surrounding areas in the South.(13) Pelargir was the main haven, as is clearly stated. During the Drowning, four ships of Elendil came to the North while five ships of Isildur and Anarion came to the South.(14) Moreover, after the Fall of Sauron and the End of the Second Age, a great deal of the Northern Dunedain were slain at the Gladden Fields.(15)

The Northern Kings therefore ruled over a lesser proportion of Numenoreans and a greater proportion of indigenous Men of Middle-earth, or Men of the Twilight. There had been Men in Eriador since the Elder Days, and the Numenoreans claimed lordship over them.(16) Since the Northern Dunedain were fewer in number, it is conceivable that they were more jealous of their lineage, and had been less likely to intermarry with those of non-Numenorean descent, and this may help explain why the Northern Line survived three thousand years.

It may also be the reason why the nation of Arnor fell. Arnor was beset from Angmar, as Gondor was from the East and South. However, Arnor never attempted to ask for aid, as Gondor did multiple times. Annuminas never attempted to contact the Men of Wilderland, as Minas Tirith did. It may have been impossible, as the Mountains were held by Angmar. Men to the South of Eriador were hostile to the Numenoreans.(17) The only help that was available was the remnant of the Noldor in Rivendell or the Havens. Not only were these Elves greatly diminished, the Elves had never intermingled with Men in any lasting form.

Arnor was alone and beset by external and internal calamities. The plague rolled through Eriador, the witch king attacked it from the East, and the sons of Earendur split Arnor into three because of “dissention.” This in and of itself may be the greatest calamity to befall the North, yet unfortunately the Professor gives us only a fragment of a sentence to explain it. Arnor faced nothing worse than Gondor did -–in fact Gondor may have faced worse challenges. Yet Gondor had something Arnor did not – the ability and the willingness to ask for immigration and outside aid from Men of non-Numenorean descent. This was the final ultimate cause of the fall of Arnor.