Duke

A duke is a nobleman, historically of highest rank below the King or Queen, and usually controlling a duchy. The title comes from the Latin dux, which had the sense of "military commander" and was employed both by the Germanic peoples themselves and by the Roman authors covering them to refer to their war leaders.

In the Middle Ages, the title signified first, among the Germanic monarchies. The dukes were the rulers of the provinces and the superiors of the counts in the cities, and later, in the feudal monarchies, the highest-ranking peers of the king. There were, however, variants of these meanings, and there were even sovereign princes employing ducal titles.

In the Modern Age, it has become a nominal rank without an actual principality. It is still the highest titular peerage in France, Portugal, Spain, the United Kingdom, and Italy.

A woman who holds in her own right the title to such duchy or dukedom, or is the wife of a duke, is normally styled duchess. However, Elizabeth II of the United Kingdom is known as Duke of Normandy in the Channel Islands.