Physical description: A plain, golden ring with an Elvish inscription only visible if placed in fire. Ring seems capable of manipulating its own size to fit each bearer.

Biography: During the Second Age, the Elven-smiths of the Noldor with the assistance of Sauron reached the height of their skill since the days of Feanor, and under Sauron's guidance they began to work on great Rings of Power. For nearly a century the Elves laboured and as they did Sauron secretely made One Ring, a ring to rule all the Rings of Power. Aware of Sauron's forging of the ring in the fires of Mount Doom in SA 1600, the Elves hid the three most powerful rings from him and the dominion he held over them with the One Ring was lessened. The other rings Sauron recovered and gave to Men and Dwarves, and slowly they were corrupted and fell under the control of the One Ring.

Two thousand years later, the Ruling Ring was cut from Sauron's finger at the battle of the Last Alliance, and taken by Isildur for his own, but the ring betrayed him and slipped from his finger while he swam in the Anduin. The Ruling Ring passed away from all knowledge for two and half thousand years, until it was discovered by Déagol the Stoor in TA 2463. Sméagol, who murdered and took the ring for his own, went into hiding in the Misty Mountains and slowly became corrupted by the ring, or 'precious' as he called it. The ring would by chance come to Bilbo Baggins the Hobbit five hundred years later, who gave it to his nephew Frodo on his Eleventy-First birthday. Realising the true nature of the Ring, Frodo Baggins under the guidance of the Council of Elrond bore the Ring into Mordor, where it was cast into the fires of Mount Doom and was utterly destroyed, along with its master.