Arathorn II is revealed as the father of Aragorn in J.R.R. Tolkien’s appendices. Arathorn was the sixteenth Chieftain of the Dúnedain and Aragorn’s father.
Arathorn married Gilraen and had Aragorn in 2931 of the Third Age. He was killed by an Orc arrow when Aragorn was only two years old. After Arathorn’s death, Aragorn was raised in Rivendell under the protection of Elrond, who kept his royal identity concealed for much of his youth.
Arathorn is easy to confuse with earlier royal ancestors. Isildur was the king who cut the One Ring from Sauron’s hand, while Elendil founded the realms of Arnor and Gondor. Arathorn belongs to the later line of northern Chieftains descended from Isildur.