A reference to either of the two great defeats of Sauron. At the end of the Second Age, after a siege of seven years, he was overcome by Elendil and Gil-galad, both of whom also died in combat. At that time the One Ring that held much of Sauron's power was claimed by Elendil's heir Isildur, and because it was not destroyed, the first Fall of Sauron was incomplete. Over the following hundreds and thousands of years, he was able to take on a new form and rebuld his forces, so that by the end of the Third Age, he threatened Middle-earth once again. The second Fall of Sauron was brought about by the final destruction of the Ring, when it went into the fires of Mount Doom. Even this could not destroy Sauron utterly, but with the loss of his Ring he was diminished to a dark but impotent spirit, never to trouble the world again.