The Making of the Rings of Power
and the End of the Second Age of the Sun
Before the Numenoreans came to Middle-Earth, Sauron, had hated the elves and wanted to control them. In a pleasing form, he persuaded the elves of Eregion to make Rings of Power. The elves made the Rings of Power guided by Sauron. The last three rings made, known as the Three were made by Celebrimbor alone, and lusted ever after them, but Sauron never touched them, for they were given to the Wise to keep secret.
Sauron betrayed them by forging the One Ring, The Ruling Ring, to rule the other Rings, and the thoughts of those who wore them, inside of Mount Doom in Mordor. To do this, Sauron had to put much of his power and will into his Ring surpassing the potency of the Elvish rings, which were very strong. But when Sauron put on the One Ring, the elves perceived him and his plan to control them. In fear and anger, they took off their rings, and never used again, the Three openly while Sauron had the One. Sauron found out that he couldn�t control the elves by the One Ring so he demanded that he be given the rings back. War ensued. These days of War were called by the elves, the Days of Flight, and the Black Years. Sauron recovered all but the Three, the rings that the elves managed to hide. Of the other Rings, he gave the Dwarves seven rings. It is said that the foundation of the seven great hoards of treasure of the dwarves were a single golden ring. To men, he gave nine because they were most susceptible to Sauron. The men who wore the Nine, became the Ring-Wraiths. Sauron made war with the elves and closed the doors to Moria against the Dwarves. The wars lasted many years, interupted by his excursion to Numenor, until the ending of the second age when Elendil created the Last Alliance between elves and men with Gil-galad, against Sauron. 
Not since the War of Wrath of the Valar against Morgoth had that many elves been to war. And never again shall there ever be.
"Then Gil-galad and Elendil passed into Mordor and encompassed the stronghold of Sauron; and they laid siege to it for seven, and suffered grievous loss by fire and by the darts and bolts of the Enemy, and Sauron sent many sorties against them. But at last the siege was so straight that Sauron himself came forth; and he wrestled with Gil-galad and Elendil, and they both were slain, and the sword of Elendil broke under him as he fell. But Sauron also was thrown down, and with the hilt-shard of [the sword] Isildur (Elendil�s son) cut the Ruling Ring from the hand of Sauron and took it for himself." [Silmarillion p 365]
In this battle, did the Second Age of the Sun come to an end, Sauron for that time was vanquished and did not assume any form for many years. And for that time, it was thought that the One Ring was lost after the demise of Isildur as has yet to be told.
