[Son of Númenor]

From Of the Rings of Power and the Third Age:

The Ruling Ring passed out of the knowledge even of the Wise in that age; yet it was not unmade. For Isildur would not surrender it to Elrond and Círdan who stood by. They counselled him to cast it into the fire of Orodruin nigh at hand, in which it had been forged, so that it should perish, and the power of Sauron be for ever diminished, and he should remain only as a shadow of malice in the wilderness. But Isildur refused this counsel, saying: ‘This I will have as were-gild for my father's death, and my brothers. Was it not I that dealt the Enemy his death-blow?' And the Ring that he held seemed to him exceedingly fair to look on; and he would not suffer it to be destroyed. Taking it therefore he returned at first to Minas Anor, and there planted the White Tree in memory of his brother Anárion. But soon he departed, and after he had given counsel to Meneldil, his brother's son, and had committed to him the realm of the south, he bore away the Ring, to be an heirloom of his house, and marched north from Gondor by the way that Elendil had come; and he forsook the South Kingdom, for he purposed to take up his father's realm in Eriador, far from the shadow of the Black Land.

But Isildur was overwhelmed by a host of Orcs that lay in wait in the Misty Mountains; and they descended upon him at unawares in his camp between the Greenwood and the Great River, nigh to Loeg Ningloron, the Gladden Fields, for he was heedless and set no guard, deeming that all his foes were overthrown. There well nigh all his people were slain, and among them were his three elder sons, Elendur, Aratan, and Ciryon; but his wife and his youngest son, Valandil, he had left in Imladris when he went to the war. Isildur himself escaped by means of the Ring, for when he wore it he was invisible to all eyes; but the Orcs hunted him by scent and slot, until he came to the River and plunged in. There the Ring betrayed him and avenged its maker, for it slipped from his finger as he swam, and it was lost in the water. Then the Orcs saw him as he laboured in the stream, and they shot him with many arrows, and that was his end. Only three of his people came ever back over the mountains after long wandering; and of these one was Ohtar his esquire, to whose keeping he had given the shards of the sword of Elendil.

(emphasis mine)