Sauron survived the destruction of Númenor and secretly returned to his realm of Mordor, soon launching a war against the Númenórean kingdoms. He captured Minas Ithil, but Isildur escaped by ship to Arnor; meanwhile, Anárion was able to defend Osgiliath. Elendil and the Elven-king Gil-galad formed the Last Alliance of Elves and Men, and together with Isildur and Anárion, they besieged and defeated Mordor. Sauron was overthrown; but the One Ring that Isildur took from him was not destroyed, and thus Sauron continued to exist.