The story
From the duchy of Norfolk in England, q.v. As an Ecuadorian island, clipping of Duke of Norfolk's Island, bestowed by William Ambrosia Cowley in 1684 honor of Henry Howard, 6th Duke of Norfolk; his son Henry, the 7th duke; or both. As an Australian island and territory, bestowed by James Cook in 1774 in honor of Mary Howard, wife of the 9th duke.
Etymology from Wiktionary, CC BY-SA 4.0.