How does Gulliver earn the title of Nardac in Lilliput?

When the Lilliputians and Blefuscudians go to war, Gulliver proves to be very useful by dragging the entire Blefuscudian fleet of ships to the shore of Lilliput, where "The Emperor and his whole Court stood on the Shore expecting the Issue of the great Adventure." When Gulliver arrives, he cries out, "Long live the most puissant Emperor of Lilliput!" The emperor gives Gulliver the land's highest honor, "Nardac.