In “The Lord of the Rings: The Fellowship of the Ring,” Isildur cut the One Ring from Sauron’s hand. He did so during the final battle of the War of the Last Alliance, after Sauron had been overthrown and Isildur’s father, Elendil, had fallen.
Isildur used the hilt-shard of Narsil, the broken sword that had belonged to Elendil. In Peter Jackson’s film prologue, this moment is presented as a decisive victory: Isildur severs the finger bearing the Ring, causing Sauron’s physical form to collapse.
The victory becomes tragic because Isildur refuses to destroy the Ring in Mount Doom. Its power overcomes him, and he claims it as compensation for his losses. The Ring later slips from his finger in the Anduin River, exposing him to Orcs and helping earn the name “Isildur’s Bane.”
A common confusion is attributing the act to Elendil or Aragorn. Elendil fought Sauron and died; Aragorn is Isildur’s distant heir. Isildur is the one who removed the Ring.