Eärnur (Q. ‘Sea-friend’), son of Eärnil II, was the thirty-third King of Gondor, and the last to take the throne until the Restoration of the Kingship at the end of the Third Age.
While Captain of Gondor, he was sent by his father Eärnil to Arthedain to aid the Dúnedain of the North against Angmar. With an Elf-host led by Círdan (and reinforcements led by Glorfindel), the Army of Gondor defeated the forces of Angmar in the Battle of Fornost. But Eärnur was shamed when his horse bolted from the presence of the Witch King, who had now become his greatest enemy.
After Eärnur became King of Gondor, the Witch King – now in Minas Morgul and embittered by his defeat – challenged him to personal battle, but the King was restrained by the Steward Mardil. Seven years later, the Witch King again taunted the King, and this time Eärnur, with a small escort, rode to Minas Morgul to meet him in battle and never returned.
Having taken no wife and thus producing no heir, the Line of Anárion was ended upon Eärnur’s death. Mardil took office after the King’s death, though neither he nor his Heirs – the Ruling Stewards – referred to themselves as King or sat upon the Throne.