King of Men

During the later Second Age, Sauron's power in Middle-earth grew immense. From his stronghold in Barad-dûr he ruled over great swathes of the East and South, and most of the Men of Middle-earth fell under his power. During this period - the time known as the Dark Years - the Dark Lord took the title 'King of Men' for himself.

Sauron's assumption of this title angered Ar-Pharazôn, the King of the Men known as the Dúnedain, who at this time held immense power of their own, dwelling in the island of Númenor far to the west of Middle-earth. When Sauron began to threaten the Númenórean settlements along the coasts of Middle-earth, Ar-Pharazôn resolved to challenge and defeat the 'King of Men' east of the Sea. He sailed a mighty fleet from Númenor and marched on Mordor with an army so strong that even Sauron could not hope to defeat it. Instead the Dark Lord humbled himself before the King of Númenor, and agreed to return across the Sea as Ar-Pharazôn's hostage.

This defeat of the so-called King of Men in Middle-earth appeared at first to be a great victory for the Númenóreans, but it would lead in the end to the destruction of their island kingdom. Sauron swayed the will of the King of Númenor and turned him toward the secret worship of Melkor, ultimately persuading Ar-Pharazôn to attempt an assault on the Valar in Aman. This foolish and hopeless attack led to utter disaster, bringing about the Downfall of Númenor. Sauron's own physical form was destroyed in that Downfall, but his spirit returned across the Sea to Mordor, and he began to once again amass the power he had held decades beforehand as King of Men in Middle-earth.