Isildur

Son of Elendil and brother of Anarion; first King of Gondor, the Southern Realm.
Isildur and Anarion were both born in Numenor to Elendil, whose father Amandil was the leader of the Faithful and one of the King’s most trusted advisors and generals.
Isildur was still very young when Sauron deceived the King by his lies and became his only counselor. At about that time, when evil was already taking hold of the Numenoreans, Isildur performed a feat which would later win him renown and praise: perceiving that Sauron would soon impose his wish of destroying Nimloth, the White Tree, on the King, Isildur stole past the guard and took the Tree’s only fruit. The guard was roused, but Isildur, receiving many wounds, made a narrow escape through the night. Soon after this foray Sauron fed Nimloth to the fire at Melkor’s temple.
As Sauron grew more impatient in his wish to bring Numenor and its people to a bitter end, conceit and madness shrouded the King’s wits and, when he ordered the gathering of the huge fleet to invade Valinor, Elendil and his sons saw there was nothing they could do to save the King from this blunder. They put up the sails on nine ships, and on them they escaped the Drowning of Numenor. With them were not only their followers, the Faithful, but also the fruit of Nimloth and the seven Palantiri. The raging waves carried Elendil’s ships northwards, while his sons’ small fleet was borne to the mouth of Anduin, where there had long been fortifications of Numenorean explorers and tradesmen.
In the days of the Last Alliance of Men and elves Isildur, now co-ruler of Gondor and Lord of Minas-Ithil, fought among his father’s army. It was he who with the hilt-shard of Narsil, cut the Ruling Ring from the Enemy’s finger. Isildur did not heed the warnings of Elrond and Cirdan and kept the Ring, for it had already woven its snare around him. He made it an heirloom of his kingdom, and would not suffer it to be harmed. It was the Ring, therefore, that spelled his doom.
In year 2 of the Third Age, having made sure that Meneldur was ready to supplant him as King of Gondor, Isildur set out northwards to claim the throne of his late father.
In Gladden Fields, however, he was waylaid by an Orc-host, for he was careless and did not set up a guard. His followers were scattered, and his three elder sons slain. Isildur himself plunged into the waters of Anduin, but that very moment the Ring betrayed him, slipping from his finger. The Orcs saw him and shot him with many arrows. Such was the bitter end if Isildur son of Elendil.
Of all his heirs, only Valandil was spared by fate, and that was because his father had left him in Imladris.