Northern Line

		Isildur
Elendur	Aratan	Ciryon	Valandil
			Seven further Kings of Arnor, from Eldacar to Eärendur
		Amlaith of Fornost	Kings of Cardolan	Kings of Rhudaur
		Fourteen further Kings of Arthedain, from Beleg to Arvedui
		Fifteen Chieftains of the Dúnedain, from Aranarth to Arathorn II
		Aragorn II Elessar

After the fall of Elendil in the first defeat of Sauron, his elder son Isildur became King of Gondor and Arnor. If history had proceeded as expected, Isildur in turn would have been succeeded by his own eldest son Elendur, and the Two Kingdoms would have remained united. In the event, a surprise attack by Orcs saw Isildur slain in only the second year of his reign, alongside his sons Elendur, Aratan and Ciryon. This left only one surviving son of Isildur in Middle-earth: Valandil, then just thirteen years old.

At this time of upheaval Isildur's nephew Meneldil held the throne of Gondor. In principle he acted as a vassal of the High King, but with Valandil a mere child, Gondor asserted its independence. By the time Valandil reached his majority in III 10, there were two independent realms of the Dúnedain in Middle-earth. Nonetheless, Valandil maintained his power in the North-kingdom, establishing the Northern Line that ran through seven further Kings after his time.

After a time of conflict the throne became divided into smaller kingdoms, and eventually even they were lost to history, but still the line of Valandil's descendants continued unbroken through the Third Age. Aragorn was the last of this Line of Northern Chieftains, the direct descendant of Isildur's only surviving son, and thus able to rightfully claim the throne of Gondor when the time came for him to do so.

For more thorough histories of the lords of the Northern Line, see the entries for High King, King of Arnor, King of Arthedain and Chieftain of the Dúnedain.