A duchy is the territory or geopolitical entity ruled by a duke, whereas his title or area is often called a dukedom. The Grand Duchy of Luxembourg is a fully independent state and its head, the Grand Duke, is a sovereign

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During the Middle Ages, after Roman power in Western Europe collapsed, the title was still employed in the Germanic kingdoms, usually to refer

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In the 19th century, the sovereign dukes of Parma and Modena in Italy, and of Anhalt, Brunswick-Lüneburg, Nassau, Saxe-Coburg-Gotha,

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See wikt:en:duke for equivalents in other European languages.

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The highest precedence in the realm, attached to a feudal territory, was given to the twelve original pairies (en: peers), which also had a traditional function in the royal coronation, comparable to the German imperial archoffices. Half of them were ducal: three ecclesiastical

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In Italy, Germany and Austria the title of "duke" (duca in Italian, and Herzog in German) was quite common. As the Holy Roman Empire of the German Nation

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Various royal houses traditionally awarded (mainly) dukedoms to the sons and in some cases, the daughters, of their respective sovereigns; others include at least one dukedom in a wider list of similarly granted titles, nominal dukedoms without any actual

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